Fruits & Nuts
Q: I found these pea pods growing on a vine in my back yard. Can I eat them?
A: I am checking with the University of Florida’s Herbarium for a positive identification as I have only seen this vine once before at Egan’s Creek. The flower cluster is lovely; slightly larger than a golf ball in shades of magenta, pink, rusty brown and white. The vine has the leaf configuration similar to wisteria. Kathy Russell, City of Fernandina Parks and Recreation, steered me towards the Native American groundnut, Apios americana, and I am inclined to agree with her. This vine can grow in partial shade or full sun; prefers low and moist woods, thickets, stream and riverbanks, ponds, marshes, meadows, and wet ravines. It is a scary thing to eat plant material from the wild but in this instance, if it is truly the groundnut, then the seeds and tubers are edible. Most of the information I have found on this plant has come from a publication by James Duke from Purdue University. According to his paper during the potato famine of 1845, Apios was introduced to Europe. Its cultivation there as a food crop was abandoned when growing potatoes again became feasible. The tuber is more slender and somewhat smaller than the typical potato as it is about 2.5 inches long. However, the tubers often grow in clusters of two to four. American groundnut was prized by early American settlers who ate them boiled, fried, or roasted. They called them groundnuts, potato beans or Indian potatoes. The Pilgrims of New England survived their first few winters by living on them. I don’t know about you but that tidbit of information was news to me. Even bread was made from the root. Indians were said to eat the seeds like lentils. American groundnut is found growing from eastern Canada and the US. It grows from Florida to Texas, north to Nova Scotia and west to Minnesota and Colorado. Like so many other vines, this species can also be “weedy” and cause problems in cultivated areas. It has been known to be a serious weed in cranberry plots (Devlin, 1981). Fernald (1958) recounted an anecdote indicating the economic value of the groundnuts to the pilgrims, "The great value to the colonists of this ready food is further indicated by a reputed town law, which in 1654 ordered that, if an Indian dug Groundnuts on English land, he was to be set in stocks, and for a second offence, to be whipped."
Q: I bit into an apple and a large portion of the area around the core was mushy and brown. It looked perfect on the outside. What would cause this?
A: I was able to locate two universities (Washington State and University of California) which have conducted studies of various types of apples. Both universities have discovered the potential cause most likely occurs after harvesting of the apples. I am sure there are other universities conducting the same research, but these two directly addressed the internal discoloring of the flesh around the core of the apple. The internal browning of apples during postharvest storage varies from year to year, but there is strong evidence pointing to how early the apples are harvested and the carbon dioxide concentration in storage atmospheres. The occurrence of internal browning was reduced when the apples were harvested within 180 days after bloom. If left on the tree longer, the potential for internal browning increased. In addition to harvesting at the appropriate time the apples needed to be stored where the concentration of CO2 was at levels below 0.5% to reduce losses from the internal browning disorder. The good news is the cause is not a pathogen such as a fungi, virus or bacteria and in most instances this problem can be avoided by proper harvesting and storage procedures. Unfortunately, you and I cannot detect this problem simply by looking at the external part of the apple – it is just the luck of the draw.
Q: What makes an apple “mealy”?
A: Don’t you hate when that happens? Like you, I have purchased a bag of apples, only to find they are not crunchy and hard – the way I like them! The flesh of the apple becomes soft and “mealy” when the substance holding the individual cells together dissolves causing mushy fruit. This type of older apple can also taste somewhat dry because the water in the cell tissues is tougher to release. When the apple is mealy it usually means it was stored improperly or has been sitting on the grocery shelves too long. It would be best if we could eat the apple immediately after it was picked but only a lucky few live where apples are grown. They usually do not hold up well in a pie or salad so use them for something else. However, do not feel too discouraged, you can use these mealy apples for cooking fritters, scones, applesauce or apple-butter.
Q: I have several acres and would like to grow apples. What kind of apples can I grow here?
A : We can grow several varieties of apple here, but they will be different than your grocery store type. But the tree itself is beautiful and well worth the effort. Apples grown here require full sun, good air circulation, and a soil pH of 6.0 to 6.5. Planting on hill tops is preferable to low lying areas because hill tops confer good air and surface water drainage. The recommended cultivars are 'Anna', 'Dorsett Golden' and 'Tropic Sweet'. Most apple cultivars are not self-fruitful; thus more than one cultivar should be planted together for cross pollination. 'Anna' and 'Dorsett Golden' originated in Israel and the Bahamas, respectively. 'Tropic Sweet' is a new patented cultivar from the University of Florida breeding program. All three varieties serve as pollinaters to each other. Fruit ripens on these three varieties from late May through June. Tree bloom and fruit ripening are generally 2 to 3 weeks earlier in north central than in north Florida. All three cultivars have good keeping quality and will last up to six to eight weeks with refrigeration. For more information look up the University of Florida publication called, “Low Chill Apple Cultivars for North and North Central Florida” or check out the website: http://edis.ifas.ufl.edu/mg368
Q: I bought several Anna apple trees because I was told they grow well here, but they really are not producing apples. What could be wrong?
A: Most apple cultivars (cultivated varieties) are not self-fruitful; thus more than one cultivar should be planted together for cross pollination. So we recommend purchasing another apple tree with the Anna such as ‘Dorsett Golden’, Ein Shemer’ or ‘Tropic Sweet.’ Relatively few cultivars of apples (Malusdomestica L.) can be grown successfully in Florida. Northern apple cultivars such as 'Golden Delicious’, ‘Red Delicious’, 'Gala', 'Fuji' or 'McIntosh' are not exposed to low enough temperatures during Florida's mild winters, to produce a good fruit. However, a few apple cultivars with a low chilling requirement can be successfully grown in Florida. Chilling requirements may be quantified on the basis of the cumulative amount of hours less than or equal to 45° F during the winter. Early morning sun for more than half the day is best with a soil pH of 6.0 - 6.5. Of the numerous apples tested by the University of Florida, only tested only 'Anna,' 'Dorsett Golden,' ‘Ein Shemer’ and 'Tropic Sweet' are recommended. Fruit of 'Anna' resembles the 'Red Delicious' more than other low-chill apple cultivars. 'Dorsett Golden' fruit resembles 'Golden Delicious,' and are slightly smaller than 'Anna.' 'Tropic Sweet' fruit are less red, firmer, less acidic and sweeter than either 'Dorsett Golden' or 'Anna'. Optimum fertilizer application rates for apple trees are largely unknown for Florida conditions. A balanced fertilizer such as 10-10-10 with micro-nutrients is recommended and applied in January and June. Regarding pruning, young apple trees should be trained to a modified, central leader system similar to standard structural trees. Attached is a publication from the University of Florida: http://edis.ifas.ufl.edu/mg073
Q: Can we grow almonds here in Northeast Florida?
A: The quick answer is - not well. A determined grower could probably grow just about anything but we really do not have the optimal conditions for the almond tree to produce abundantly. Almond trees, Prunis dulcis, prefer warm, dry summers and we have hot, humid summers. This tree produces its flowers in February or March. If it experiences any frosts during the flowering time, the potential for fruit that year is lost. It has the several disease problems and insect issues similar to peach trees – especially borers. In addition, it requires frequent fungal applications like many other fruit trees and it must be checked frequently for insect damage. There are some people who plant almond trees simply because the flowers are so pretty while knowing it will probably never produce nuts. Almonds are commonly grown in California and take about 180-240 days to harvest. Pruning should be done from December through January. Trees must be pollinated which is usually done by bees. Normally, it is suggested planting three different varieties to get good cross pollination and increase production.
Q: What is the best way to grow apricots from seed?
A: We would discourage you from trying to propagate and grow apricots from the seeds you purchased in the local grocery store. These seeds are often hybrids and are generally not suited for our warm climate. Most of the apricots produced in the United States come from California. Some historians believe the original apricots came from northeastern China near the Russian border.Apricots, like other stone fruits, need a period of time when they are exposed to cold temperatures. Most often we do not have enough long, cold periods to produce good peaches, apricots and cherries, which are all examples of stone fruits. Research is ongoing with a variety of apricot species from Thailand that have shown to possess some potential to grow and reproduce here in Florida, however the research is still in the early stages. We currently have a few peach varieties that will grow in our area such as Flordadawn or Flordaking. For more information check out the University of Florida’s publication titled: “Deciduous Fruit for North Florida”.
Q: Can I grow apricots here in North Florida?
A: Apricots, like peaches, require a certain number of “chill” hours before they will produce fruit. At this point the University of Florida is still working on a subtropical, low-chill variety from Thailand and I am not sure they are available for retail sale. After checking with several local nurseries throughout this area I was unable to find any nurseries selling apricots trees, although a few Georgia nurseries have them available. Apricot trees can be found occasionally in local garden centers but these are better grown in zones 4 - 7. Remember, we are zones 8b (Westside of Nassau County) and 9a (Eastside of Nassau County). That means this plant would possibly be under some undue stress in our region. Placing a plant outside its normal growing zone increases its chance for insect and disease infestation. What may happen with this plant is the first couple of years it may do well but produce very little fruit then in subsequent years it may decline as borers or disease attack it. Now that I have told you the “bad” news, you might consider trying one or two trees because there are always exceptions and micro-climates where trees and plants surprise us by thriving very well. Good luck and keep me posted on your progress.
Q: Can we grow avocado here in north Florida?
A: Avocado, Persea americana, is grown commercially in south Florida and many homeowners enjoy having a few avocado trees in their landscape as well. It is possible to grow avocado here but your selection of a specific cultivar will be essential for your success. Be sure to plant the trees in a protected area away from cold north winds and salty sea breezes. The varieties that can tolerate the coldest temperatures are from Mexico such as 'Brogdon', 'Ettinger', 'Gainesville', 'Mexicola', and 'Winter Mexican' which are able to survive infrequent temperatures in the low 20s. 'Tonnage', 'Taylor', 'Lula', 'Kampong', 'Meya', and 'Brookslate' may be planted in areas with temperature ranges of 24°F-28°F. Moderately cold-tolerant types (25°F-30°F) include 'Beta', 'Choquette', 'Loretta', 'Booth 8', 'Hall', 'Monroe', and 'Reed'. It might work best if you plant two different tree varieties to assist with pollination (see the publication listed below for specific directions). Trees should be planted in full sun in well drained soil, these plants do not like wet feet. Fertilize using 6-6-6-4 once every 1-2 months. Young trees should be irrigated twice a week if no rainfall occurs. It is important to irrigate on a consistent basis when trees are fruiting and certainly more water is needed on newly planted trees. Check out the UF/IFAS publication on avocadoes for the homeowner for additional information: http://edis.ifas.ufl.edu/MG213
Q: What kind of bananas can I grow in North Florida? Can you give me a little history on how they got here?
A : Bananas are vigorously growing, monocotyledonous herbaceous plants. There are two species of banana, Musa acuminata and M. balbisiana, and most banana cultivars are hybrids of these species. The banana and plantain are native to Southeast Asia, where they have been cultivated for thousands of years. Recent evidence suggests bananas were introduced into the New World ( Ecuador) by Southeast Asians around 200 B.C., and more recently by Portuguese and Spanish explorers in the early 16th century. Bananas have been grown in scattered locations throughout Florida since their introduction during the 16th century. Bananas flourish under uniformly warm to hot conditions. Fruit growth is best at 84 o F to 86 o F (29-30 o C). Plant growth slows below 60 o F (16 o C) and stops at 50 o F (10 o C). Symptoms of chilling injury (temperatures below 60 o F/16 o C but above 32 o F/0 o C) include failure of the flowering stalk or fruit bunch to emerge, development of a dull yellow or greenish-gray color to ripening fruit, distorted fruit shape, and an increase in fruit rotting. As you can see, we are already in the temperature “danger zone”. Bananas do best on flat, well drained, deep soils high in organic matter with a pH of 5.5-7.0. The most important factor is soil drainage. None of the cultivars listed in the UF publication are recommended for this area, but if you have a protected area and you are very diligent you may have some success with this plant. Check out http://edis.ifas.ufl.edu/mg040 for more information.
Q: This last bout of cold weather has caused my banana leaves to turn brown. Will my plant die?
A: Banana is best grown in cold hardiness zones 9b – 11 but it can produce fruit in USDA hardiness zones 8b and 9 when winter temperatures stay above freezing. We had a few days this winter that were well below the freezing mark, which is why you are seeing damage on the leaves. Don’t be too eager to cut back all the foliage yet, wait until we little have chance of more freezing temperatures. Plants killed to the ground which sprout from the soil in the spring will not produce fruit until the following year. Banana trees grow best on fertile, moist soil, so you may have to add some organic matter to our sandy soils. They respond well to regular fertilization. If the trees are in the landscape area around lawngrass then they probably receive sufficient irrigation. Bananas will thrive in full sun or partial shade but in our area they should be protected from both wind and cold. Too many suckers should not be allowed to develop since this will decrease the ability of any one plant to produce a good bunch of fruit. By allowing suckers to develop only at periodic intervals, a succession of fruiting can be obtained. Banana bunches should be harvested when the fruit is still green and allowed to ripen in a cool, dark place. The easily-grown Banana tree is ideal for planters near the pool, located around garden ponds, or clustered together for an exotic effect. The flowers are reddish-purple, which is always a surprise when compared to the soft yellow color of the mature fruit.
Q: What are some blueberry varieties that will do well in our area?
A: Blueberries require a soil pH of 4.0 to 5.5. At higher soil pH values, tissue levels of micro-elements such as iron and zinc become deficient. Deficiency symptoms develop on new growth and plants lose vigor. If you are not sure about your soil pH, bring in a sample to the Extension office and we will test it for you. The best time to plant blueberries is from mid-December to mid-February but often they are only available now in the local garden centers. If you purchase them now, go ahead and put them in the ground. Be sure you check for circling roots and make the appropriate cuts if they are found. It is very important to not plant blueberries too deeply as this will cause problems in the future. Apply a 2-3 inch layer of pine mulch to help lower pH, but be sure to keep it away from the trunk of the shrub. We would recommend you select rabbiteye varieties as they are less susceptible to root rot and are more drought tolerant. Rabbiteye produce later in the year which means they are not as susceptible to freeze damage. It is important so select at least 3 different varieties of rabbiteye as they require cross pollination to produce the desired fruit. When putting the shrubs in the garden allow seven feet between each shrub. Early season varieties are ‘Beckyblue’, ‘Climax’ and ‘Bonita’. Purchase some late bloomers such as 'Brightwell', 'Powderblue', 'Tifblue' and 'Woodard' which produce very well in our area. You should have no trouble locating any of these varieties. I would encourage any homeowner to grow blueberries as they are very easy and provide wonder fall leaf color once the delicious berry is gone.
Q: My blueberry bush is not doing well. I have enclosed photos, what could be wrong?
A: Your blueberry bush probably has Blueberry stem blight, which is caused by Botryospheria dothidi. This disease has caused significant plant mortality of some southern highbush cultivars in Florida. The causal fungi are usually present in orchards and blueberry fields and cause a number of different diseases on various host plants. Rabbiteyes are usually not seriously affected by this disease but some southern highbush cultivars are extremely susceptible. 'Misty' appears to be more susceptible to infection and death by blueberry stem blight than most other southern highbush cultivars. 'Misty' tends to produce very heavy crops, even as young plants. Over-fruiting predisposes blueberry plants to stem blight. There is no chemical control for blueberry stem blight. Pruning out infected wood and removing flower buds and fruit from young plants, pruning mature bushes to thin crop loads, and minimizing drought and other plant stresses appear to be the best methods of control. If the plant does not survive you might consider replacing it with a hardier rabbit-eye variety better suited for this area. Attached is a publication from the University of Florida/IFAS called “Blueberry Gardener’s Guide.” http://edis.ifas.ufl.edu/mg359
Q: I want to grow some blueberries but I am not sure what type is best.
A: Two types of blueberries are grown in Florida ; southern highbush and rabbiteye. Rabbiteye blueberries grow best in regions north of Ocala . Cross pollination between, or among, varieties is needed for maximum production for both types of blueberries. Therefore, multiple varieties of rabbiteyes are needed to pollinate other rabbiteyes. On suitable blueberry soils in north and north central Florida , rabbiteye blueberries are more vigorous, longer lived, and easier to care for than most southern highbush varieties. Rabbiteyes are more drought tolerant and can grow satisfactorily in soils lower in organic matter. The soil pH should be around 4.5, which is very acidic. I am currently growing mine in pine bark and having great success. Southern highbush has a tendency to succumb to root rot and blight, I lost two trees to blight the first year I planted them. Severe crop losses to spring freezes are not uncommon in north Florida , especially for early-season rabbiteyes which bloom before mid- to late-season rabbiteyes. For home gardeners and u-pick growers, late flowering varieties such as Powderblue and Brightwell usually produce abundant crops without freeze protection at most locations in northern Florida . Rabbiteye fruit is generally firmer than southern highbush however, berries of highbush and rabbiteye are enough alike that most consumers do not distinguish between the two. Early-season rabbiteye varieties are Austin , Beckyblue, Bonita, Climax, and Premier. Mid-late season varieties are Brightwell, Chaucer, Powderblue and Tifblue. If you plan to grow blueberries it would be advisable to have your soil tested by the University of Florida . Stop by one of our offices and pick up a soil test kit. It cost only $7 and well worth the investment. Callahan Extension office is 543350 U.S. Highway #1 , 904 530-6353 (on the fairgrounds) or the Yulee satellite office 86026 Pages Dairy Road, (904) 530-6350. Check out the University of Florida publications on blueberries for more information on selection and care http://edis.ifas.ufl.edu/HS215 or http://edis.ifas.ufl.edu/mg359
Q: I am losing my blueberry bushes, several have died already. I purchased the shrubs locally at a franchise store. They were labeled “Southern High Bush.” What is wrong?
A: Southern high bush blueberries common develop a disease called Blueberry Stem Blight, caused by Botryospheria dothidia. This disease can cause the death of some southern highbush cultivars in Florida. Rabbiteye varieties are usually not seriously affected by this disease but some southern highbush cultivars, such as ‘Misty” are extremely susceptible. 'Misty' tends to produce very heavy crops, which predisposes blueberry plants to stem blight. There is no chemical control for blueberry stem blight. The best control method is to prune out infected wood and remove flower buds and fruit from young plants. Mature bushes should be thinned by pruning out limbs with heavy crop loads. Irrigate plants on a regular basis to minimize drought stress but remember blueberries are susceptible to root rot if over-watered.
Q: My rabbit-eye blueberries have almost totally completed fruiting. When should I prune them?
A: I am amazed, in this heat, to hear you local gardeners are still out there working in the yard. Congratulations to you. Of course, I am still pulling weeds each time I walk by my perennials and blueberry garden too. I am attaching a publication on pruning blueberries. Consider pruning directly after all the berries have been harvested. However, there is some research which indicates an increase in fruit production if the plant is pruned every other summer. Pruning during dormant season will reduce the amount of fruit therefore it is not normally recommended. I hand prune my blueberries unlike many orchard growers who will use large machines to cut off the tops of the shrubs to keep them from growing too tall. The publication attached has some really good illustrations on how those pruning cuts should be made. Remember, blueberries prefer an acid soil with the pH between 4.5 and 5.5. If your soil is too alkaline, consider growing blueberries in a combination of pine bark and peat. http://edis.ifas.ufl.edu/hs223
Q: Can you identify this plant and is it poisonous to my horses?
A: The specimen you brought to the office was probably a wild or black cherry tree, which is common in Northeast Florida. According to Cornell University, whose site I visited, any of the cherry trees would be a problem for your horses as well as cattle, moose, sheep, swine, and goats. The primary poisons are amygdalin and prunasin, which are found in the leaves and the seed of the cherry tree. We discussed removing lower limbs but the best solution would be to remove the tree as it produces numerous fruit which would fall to the ground and still be potentially ingested by the horses. This is an example of better safe than sorry. For a complete list of plants horses should avoid please visit the Cornel website: http://www.ansci.cornell.edu/plants/php/plants.php?action=display&ispecies=horses
Q: I think I have rust on my figs, what should I do?
A: Fig rust, caused by the fungus Cerotelium fici (formerly Physopella fici), is the most common disease of figs in most regions of the southeastern U.S. Fig rust occurs only on the leaves and does not affect the fruit directly. Rust generally develops late in the summer, and in years when disease is severe, it can cause the trees to defoliate in a matter of a few weeks. If this happens on a regular basis, the overall growth of the trees can be reduced and yields can be affected. Initially, symptoms of fig rust are visible as small, yellowish spots on the upper surface of the leaves. As these spots (or lesions) grow larger, they turn a reddish-brown color but remain relatively smooth. On the lower surface of the leaf, the lesions are a reddish-brown color and have a slightly raised, blister-like appearance. Heavily infected leaves often turn yellow or brown, particularly around the edges, and drop prematurely. There are no fungicides registered for use on edible figs in Florida so this is one of those conditions we call “grin and bear it.” It is important to remove and throw away infected leaves once they fall to the ground but little else can be done.
Q: What is the best type of fig tree to grow in our area?
A: The fig tree was first introduced to the Americas in 1575 by Spanish explorers in Florida. The fig is a deciduous tree that can reach 50 feet in height but most often grows to 25 feet due to periodic cold injury to the trunk and limbs. Most fig trees in the southeastern United States are multiple-branched shrubs. Fig wood is weak and decays rapidly. When branches are cut or damaged, they produce milky latex which can cause skin rashes. This latex contains a protein-degrading enzyme called ficin, which is similar to papain. Fig trees produce roots which can be very deep in well drained soils. Brown turkey and Celeste are the preferred cultivar for our area as they are more cold- hardy. Fig cultivars recommended for Florida belong to the common types of fig and are parthenocarpic which means the fruit develops without pollination. The University of Florida recommends a “closed eye” fruit type as this minimizes the chance water will enter into the developing fruit thereby reducing the opportunity for fungal decays. Fertilize trees between February and August using 10-10-10 which contains minor nutrients for fruit bearing trees. Allow plenty of room for this tree and be sure to place it in an area where the soil is well drained. The tree requires no pruning to encourage fruiting. For more complete information, check out the University of Florida publication on figs: http://edis.ifas.ufl.edu/mg214
Q: When do I prune and fertilize figs?
A: Figs are deciduous trees which can reach heights up to 30 feet but figs seldom attain tree size in Florida. When frozen to the ground, they sucker from the base and form a bush. Lateral spread of roots is quite extensive and, in certain soils, roots are quite deep. Shoot growth is vigorous, producing soft wood that is susceptible to cold damage. Prune only to maintain desired bush size, heading back to promote branching. Keep 3 - 5 leaders, removing any suckers. Prune freeze-damaged wood after regrowth commences. Prune all dead wood and remove branches that interfere with the leaders’ growth. Do not leave bare, unproductive stubs when you prune. These stubs are entry points for wood decay organisms. Make all pruning cuts back to a bud or branch. Little is known about specific fertilizer needs, but figs respond well to small amounts of mixed fertilizer applied once a month during growing season.
Common types are recommended for Florida because they do not require pollinators to produce fruit. Desirable characteristics include a closed eye to prevent insect and water entry, a long fruit stem allowing fruit droop which prevents moisture entering through eye, green skin color results in less bird damage and nematode-resistant rootstocks.Some potential choices are: 'Celeste', ‘Brown Turkey’ and ‘Green Ischia’. “Celeste’ is also called Celestial, Blue Celeste, Little Brown, or Sugar. This variety is widely grown in the South. Celeste produces small, purplish-bronze to light brown fruit with closed eye, which ripening from mid-July to mid-August. ‘Brown Turkey' is often sold as Everbearing, Harrison, Ramsey, Lee's Perpetual, Eastern Brown Turkey, or Brunswick. ‘Brown Turkey’ rivals 'Celeste' in popularity. It produces moderate size fruit of bronze color with medium eye opening, which ripens in late July until late fall and will fruit following severe freeze damage. 'Green Ischia' is sold as Ischia Green, White Ischia, Ischia Verte. ‘Green Ischia’ is not widely grown but green color and closed eye make it desirable. Fruit ripens late July to early August but it does not fruit following a severe freeze.
Q: My fig tree is just about to finish bearing fruit. It has grown so large that I realize I need to prune it. When would be the best time? I do not want to lose any possible fruit for next year.
A: The best time to prune fig trees is immediately after the tree has finished fruiting and you have picked the last ripened fruit. It is important to note that figs do not require pruning to increase the amount of fruit. If you feel the tree has become too overgrown then you can prune it but do not remove too much of the tree branch. Pruning now will allow for new bud growth and the opportunity for continued fruit production for next year. Other fruit trees such as citrus, apple or pear should be pruned late winter or early spring. You may remove all dead or decaying limbs any time of year. When you make your pruning cut, be sure to prune back to just above where a bud will form. Do not leave a stub as this will increase the opportunity for splitting, cracking and introduction of disease into the stem. Always sterilize your pruners to avoid transmitting diseases from one branch to another.
Q: What is this spiked fruit I found growing in the mucky area behind my office?
A: I am glad you brought a sample to the office. I believe the spiked fruit is the horned melon or kiwano, Cucumis metuliferus. Horned melons are produced on vines which were originally from southern and central Africa. The foliage is evergreen in its native country but it will die back in North Florida’s cooler temperatures. The fruit are about the size of a large pear which starts out light green in color but changes to yellow-orange as it matures. The spines on the outer rind are quite sharp, which made handling the fruit difficult. However, the rind was malleable and easy to cut in half using a utility knife. The interior pulp is a pale green color with many seeds covered by a runny, gelatinous substance. The interior pulp has been described as tasting similar to a cucumber with a hint of lime. Other descriptions include the adjectives bland and slimy, which was enough to keep me from tasting it. Be warned, I would not recommend anyone eat the fruit of a wild vine unless they had botanical confirmation of the specific cultivar. There is no need to take an unnecessary and unscheduled trip to the emergency room.
Q: What can you tell me about the common garden huckleberry?
A: The University has a publication on the garden huckleberry in the genus Solanum. It is an edible form of the common nightshade weed plant. Parts of many nightshade plants can be poisonous as they can contain high levels of poisonous alkaloids. Because of its close relationship with the nightshade family there has been some confusion about ingestion of the fruit of this plant. It is always best to avoid eating fruit or berries from shrubs or trees in the forest unless you are well acquainted with the plant. However, garden hackberry is safe to eat. Garden huckleberry is also known as quonderberry, wonderberry, sunberry, moralle, morella, petty morel, solanberry, black berried nightshade, and houndsberry. The reference to black berried nightshade is very similar to deadly nightshade which is poisonous. The garden huckleberry plant looks similar to a pepper plant growing to about 2½ foot tall. The berries are green when immature and black when mature, resembling wild huckleberries. Berries are filled with a greenish pulp, mixed with small pale yellow seeds. The berry flavor is similar to a bitter tomato, which does not sound appealing to me. The berries can be used for making preserves, pies or cooked dishes. Garden huckleberry has been grown in gardens successfully all around Florida. Sow seeds about 1-inch deep at a time, which will allow the plant to grow and mature in warm weather since it is susceptible to cold injury. Space plants 12 to 24 inches apart. It may be transplanted, and a start may be obtained from a cutting. It has few pest problems.
Q: I would like to grow kiwi here. What can you tell me about it?
A: There are many problems with growing kiwifruit in Florida. The first is kiwifruit grows naturally at altitudes between 2,000 and 6,500 ft., most of Florida is at or below sea level. Ideal winter temperatures are 40 to 57 degrees with summer temperatures no higher than 77 degrees. During the winter, if temperatures fluctuate between warm and cold, blossom drop can occur which will reduce fruit production. The fruit is produced on “female” vines and requires a “male” vine for pollination. One male vine can pollinate as many as eight female vines. One of the biggest pests of kiwifruit is root knot nematodes, which are very common in our sandy soil. There have been several attempts to grow kiwifruits in northern and central Florida, and a few vines are growing experimentally in the southern part of the state and even on the Florida Keys but, so far, only the plants at Tallahassee have fruited to any extent. One other note, the fuzzy kiwifruit, Actinidia chinensis, found in grocery stores is from China. Actinidia arguta, also called hardy kiwifruit, is grown in the United States. The fruit have similar tastes but A. arguta, does not have to be peeled and can be eaten straight from the vine.
Q: I did not remove all the kumquats off my tree before the freeze. Some of them look wrinkled and white but others look firm and orange. Are they safe to eat?
A: The citrus fruit is most likely safe to eat but the white ones are showing freeze damage and the taste will not be very appealing. It would be best to remove all the freeze damaged fruit and either throw them away or use them in your compost bin. The orange colored fruit should probably be picked also so it can be enjoyed now before our next expected freeze. If you are interested in learning more about growing citrus in Nassau County, please attend the Landscape Matters class I will be holding at 10am on January 12 at the Yulee County Building. The session is free of charge.
Q: What is on my kumquat fruit?
A: Normally, we would not suggest you bring citrus to the Extension office because of the possibility of transferring citrus canker. However, since you placed the citrus in a sealed freezer bag I felt confident it did not pose much of a threat. Your kumquat has Soft Brown Scale - Coccus hesperidum L.citrus. The scale body is flat and oval, light brown to yellowish in color with brown stippling, and 2.5 to 4 mm long. It was so small that I thought at first this problem was scab. I was glad I took a second look to discover soft brown scale. This scale gives birth to pale yellow crawlers, but you can imagine how small they must be when compared to the adult female. Males are uncommon. Soft brown scales secrete large amounts of honeydew and the adjoining foliage becomes heavily coated with sooty mold, which was the case in your tree. On occasion, young citrus trees can be killed by high populations of soft brown scale from feeding and honeydew production but you should be able to manage your infestation. Scale feeding on older trees can result in reduced tree vigor, twig dieback, reduced yields, and lower fruit grades due to heavy sooty mold. Soft brown scale can be found infesting a wide range of ornamental plants in addition to citrus. The scale is heavily parasitized by several different species of parasitic wasps.However, if pesticides are used heavily, the predators are often killed off while the pest seems to flourish. Populations of this scale often build up after several years of mild winters, which we have had until this year. It is best to apply “softer” chemicals such as Insecticidal soap on the young nymphs (tan in color) during the months of April-May. Again, it is best to avoid using strong insecticides on these trees as that presents a problem farther down the road when control will be important.
Q I left some of the kumquat fruit on my tree and with the extreme cold weather over the last few weeks, some of the kumquats froze on the tree. Now, I am seeing some of the fruit with large, black spots, others have turned white and collapsed onto themselves. What should I do with this fruit?
A: The same thing has occurred to the tree in our demonstration garden. I have been removing the damaged fruit as it can be a source of fungal disease which can easily be passed to other parts of the tree. The fruit is not good to eat so I would recommend you take all the damaged fruit off and compost it or throw it away. No reason to take a chance at potentially spreading disease. Any fruit which does not appear to be damaged, I would leave on the tree until it has matured. One of the nice things about kumquat fruit is it can remain on the tree for longer periods of time than other citrus like Satsuma.
Q: Can we grow mulberries here in Northeast Florida?
A: Indeed, we can grow mulberries here. Mulberry (Moras spp.) is a fruit producing tree that can provide gardeners tasty fruits. Native red mulberry trees have been enjoyed by people in North America for centuries. On expedition in the mid-1500s De Soto observed Muskogee Indians eating dried mulberry fruits. Over winter the Iroquois mashed, dried, and stored the fruit to later add to water, making warm sauces that were occasionally mixed into cornbread. Cherokees made sweet dumplings by mixing cornbread and sugar with mulberries. The Timucua people of northeast Florida used the fruit, along with the tree's leaves and twigs, to make dyes, and the Seminoles used the branches to make bows.
When choosing a location, keep in mind fallen fruits stain the hard surfaces, so it's best to avoid planting over driveways, sidewalks and patios. Selecting a light-fruited cultivar can also cut down on the mess factor; look for 'Tehama' or 'King White Pakistan'.
Mulberry trees require very little maintenance; they rarely require irrigation after establishment and generally do not require fertilization. As far as pruning goes, you can perform light pruning when trees are young to help create a strong framework of branches. With a mature tree, you should only prune to remove dead or damaged wood or crossing limbs, since the wounds caused when removing a major branches are slow to callous. Be careful when pruning your tree, mulberry trees have milky sap which can causes skin rashes in some people.
Q: Are my grapes Scuppernong or muscadine?
A: The muscadine grape (Vitis rotundifolia Michx.) is native to the southeastern United States and was the first native grape species to be cultivated in North America. The natural range of muscadine grapes extends from Delaware to central Florida and occurs in all states along the Gulf Coast to east Texas. Muscadine grapes will perform well throughout Florida, although performance is poor in high alkaline soils or in soils with very poor drainage. These grapes do not like to be in areas where water is likely to drain off slowly or near retention ponds. There are three species within the Muscadania subgenera (Vitis munsoniana, Vitis popenoei and Vitis rotundifolia ). Wild muscadine grapes are functionally dioecious meaning they have male and female vines. Male vines account for the majority of the wild muscadine grape population. Muscadine grapes are late in breaking bud in the spring and require 100-120 days to mature fruit. Typically, muscadine grapes in the wild bear dark fruit with usually 4 to 10 fruit per cluster. Bronze-fruited muscadine grapes are also found in the wild, and they are often referred to as scuppernongs. There are hundreds of named muscadine grape cultivars from improved selections, and in fact, one that has been found in the Scuppernong river of North Carolina has been named Scuppernong. So to directly answer your question, not all muscadines are Scuppernong but all Scuppernongs are muscadines and yours is a muscadine. How about that for a tongue twister! There are over 100 improved cultivars of muscadine grapes varying in size from 1/4 to 1 1/2 inches in diameter and 4 to 15 grams in weight. Skin color ranges from light bronze to pink to purple to black. Flesh is clear and translucent for all muscadine grape berries. One reason for the popularity of muscadine grapes is that they are a sustainable fruit crop in the southeastern United States. They are tolerant of insect and disease pests, and homeowners can successfully grow muscadine grapes without spraying any pesticides. For more complete information on planting, fertilization, pruning, etc. look over the following UF/IFAS publication: http://edis.ifas.ufl.edu/hs100
Q I bought some expensive merlot grape vines and was told I could grow them here. However, they are just sitting in the ground and not growing at all. I was hoping they would spread quickly and cover my arbor.
A: There are always exceptions to what we recommend growing here and what might actually survive. However, there are some limitations based on the plant varieties, soil types and overall climate conditions which restrict what we really should try to grow here. We easily grow Muscatine grapes. Some of the Muscatine grapes are grown for their fresh fruit and others for their ability to make wine. Unfortunately, we really cannot grow the type of grapes used for fine wine making similar to those grown in Europe or California. Merlot, for example, prefers mild climates with long, hot, dry growing seasons and moderate winter temperatures. While we often have mild winters, we seldom have the hot, dry growing seasons. We are far too humid and often too wet for these grapes to do well. In addition, some of the Merlot grapes prefer cool, deep sandy loam – we have warm, sandy soils. The soil needs to hold moisture but cannot be wet. You could easily cover your arbor using a muscadine or even a wild grape variety. I have attached the University of Florida publication on muscadine grapes to better inform you about your potential choices. http://edis.ifas.ufl.edu/pdffiles/HS/HS10000.pdf
Q What is eating my grape vine?
A: Most likely the holes you see in the grape leaves are from the larvae of the Grape Flea Beetle, Altica chalybea (Illiger) or possibly Altica woodsi. Apparently, Altica woodsi, feeds on the underside of leaves, which is just what your larvae are doing. This flea beetle is so common it is found throughout most of the United States. Adults are dark metallic greenish-blue jumping beetles about 4-5 mm (1/5 in) long. They feed on buds and unfolding leaves. The larvae are brownish and marked with black spots. Larvae feed on flower clusters and skeletonize leaves. The larvae of these beetles also will eat Virginia creeper, apples, ashes, birches, elms, pines, and oaks. No wonder is it so common since almost any landscape will have at least one of these plants. Damage is often restricted to vineyard borders, particularly near wooded areas. Clearing uncultivated woodlands near the grapevines and removing weed species between the rows are preventative/control methods that can be used for grape flea beetle. To date, no monitoring guidelines have been developed. Some biological and neonicotinoid insecticides will reduce high populations of flea beetles during the growing season.
Q: I am interested in growing muscadine grapes for eating but not wine making. I really can not tell the difference by looking at the grape. Can you help me choose which ones would grow best here in Northeast Florida?
A: Muscadine grapes are fairly easy to grow here with little effort aside from pruning to increase the amount of fruit. Muscadine grapes are a wonderful addition to any home garden as these hardy grapes have few disease or pest issues, which normally plague other fruit varieties in our region. The best fresh (eating) muscadine grapes should be large, thin skinned, and most importantly – sweet. The top cultivar choices for fresh muscadine grapes are Fry, Farrer, Nesbitt, Southern Home, and Summit. Although you mentioned not wanting to make wine you might be interested in growing other muscadine grape jelly varieties such as Carlos, Doreen, Golden Isles, Noble, and Welder. Many gardeners make delicious jellies and much pride is derived from entering these prize jellies into county fairs. You seem like the adventurous type so you might want to try your hand at jelly making. The following is a publication from LSU on muscadine jelly making: http://www.lsuagcenter.com/NR/rdonlyres/EFF15CFB-32FB-4102-AE05-545A5FB9463B/2156/pub2422muscadine3.pdf
For complete information regarding planting, irrigation, fertilization and pruning of muscadine grapes please check out the University of Florida/IFAS publication titled, “The Muscadine Grape” by Andersen, Crocker and Breman attached below.
Q: When do I prune my muscadine grapes?
A: Muscadines should be pruned between January and March in the Northeast Florida area. According to a publication by the University of Florida you should prune any branches that are less than 3/16 inch in diameter, leaving 2 to 3 buds per spur. Remove most of the spurs located at the top of the trunk to prevent crowding and bushiness, which will interfere with harvest. Prune any arms that are not vigorous. Application of fertilizer should occur in late March, May and just after harvest. Apply no more than 4 to 6 pounds of 6-6-6 or 8-8-8 per vine per year. Split applications are more efficient than a single application. Muscadines mature in August and early September and should be stored at cool temperatures until eaten or used for jellies or wine.
Q: I have muscadine grape vines and I would like to know when I should prune them.
A: This information comes directly from a University of Florida publication on muscadine grapes. “The shoots of muscadine grapes arise from buds in the leaf axils of past season's growth. The fruit of muscadine grapes is comprised of 6 to 12 berries per clusters on current year’s growth. Flowers appear after several weeks of shoot growth usually in late April. Muscadine grapes seldom sustain frost injury in the spring due to their late bloom date. Certain cultivars are susceptible to winter injury if a drastic decline in temperature occurs before the vine is acclimated to cold winter temperatures. Pruning in November or December can exacerbate the degree of winter injury. For this reason the best time to prune is mid-February to mid-March. Normally most vines, when acclimated can tolerate temperatures down to about 15°F without injury. After a grapevine has been trained to a desired configuration it must be pruned to keep it manageable and to ensure maximum vine performance. As indicated above, major pruning is normally done during the dormant season, although touch up pruning can be done during the growing season. You may notice that pruning cuts bleed when soil temperatures are high, but there is no evidence that this is injurious to the vine.”
Q: I bought one Concord grape and one muscadine grape vine. How do I care for them?
A: The biggest obstacle to growing the concord grape is the high potential for disease in our hot, humid environment. You can try them but realize if you are not successful it really is because the plant is not suited for this area. Muscadine grapes will do quite well here and you should be very pleased with the results. The article attached discusses the difference between bunch grapes and muscadine. There is an actual genetic difference between the two types of grapes. Bunch grapes have 38 chromosomes and produce fruit in the clusters (30 – 100). This form is the type of which we are most familiar. Bunch grapes are harvested in clusters. Muscadine grapes have 40 chromosomes which produce 2-10 berries but the grapes are picked individually. Some good muscadine grape varieties to use for wine, jams and jellies are Alachua, Carlos, Noble, and Welder. Muscadine grapes preferred for eating are Black Beauty, Fry, Black Fry, Granny Val, Farrer, Pam, Pineapple, Pollyanna, Southern Home, Summit, Supreme, Sweet Jenny and Tara. http://edis.ifas.ufl.edu/pdffiles/HS/HS10000.pdf; http://edis.ifas.ufl.edu/pdffiles/AG/AG20800.pdf
Q: Can we grow olives here?
A: It appears we can. We have two olive tree/shrubs planted in the Fruit Demonstration garden and this year we have a few olives on one of the trees. The fruit turns green in the summer and should ripen and turn black in the fall. The olive originated in the eastern Mediterranean area, and has been cultivated by man since ancient times. Trees are extremely long-lived, up to 1,000 years, and are tolerant of drought, salt and almost total neglect. Olive trees have been reliable producers of food and oil for thousands of years. Earliest references of olive oil use and international trade date to 2000-3000 BC. The olive was spread throughout Mediterranean Europe and North Africa very early, due to its ease of vegetative propagation and cultivation in dry climates. The Romans built on earlier work on olive culture by Greeks, Arabs, and Egyptians, and refined olive oil extraction and improved cultivars used for oil. Today, the industry remains largely confined to Mediterranean countries of Europe, the Middle East, and North Africa, where it began thousands of years ago. The California industry began in the late 1800s as settlers planted orchards from cuttings taken from the original trees planted at Spanish missions. By 1900, there were about ½ million trees being grown in California, largely for olive oil production, but shortly thereafter, pickling and canning procedures were developed for producing black olives, the primary olive product from California today. The trees appear to have no insect or disease issues. Olive might be a good choice to consider as a hedge as long as we consider keeping it at a 6-10 foot height. Check out our website for more complete information on our olive tree: http://nassau.ifas.ufl.edu/horticulture/fruit/olive.html
Q: I lost my peach tree this year. When I dug it up I noticed a large growth just at the surface of the soil. What could the growth have been?
A: I appreciate the photo you sent and I suspect the culprit is most likely a disease called Crown gall. Crown gall is commonly found as growths on the roots or stems of plants in the rose family especially the genus Prunus. Prunus includes many of the fruit trees such as peach, plum and apple. In fact, it has been found on more than 600 plant species, so you can imagine the economic devastation it can cause to homeowners and commercial growers. Since it is located near the root attachment to the stem it greatly reduces, if not stops, the necessary water and nutrients from getting to other portions of the plant. This can cause stunting, leaf and fruit drop or lower fruit quality and production. The cause of the disease is a bacterium which is normally found in the soil. Any wound to the root or stem structure during planting will allow a place for the bacterium to enter into the plant and become established. There is no chemical treatment for the disease. I would remove the plant and destroy it. This bacterium can live in the soil for over two years so I would be careful about planting another tree or shrub from the same family at this site. But more importantly it is best to be extremely careful when planting new trees and shrubs to avoid damaging the stem.
Q: My peach tree is looking anemic. What could be wrong?
A: I am glad you brought in a soil sample so we could test the soil pH for you. We discovered your particular soil was alkaline (over 7.0). Most of our fruit and vegetables prefer a slightly acid soil which is between 6.0 and 6.5. When the soil becomes alkaline, often there are limitations to the absorption availability of some nutrients through the roots of the tree. Iron is one of those nutrients. It is involved in the manufacturing process of chlorophyll (the green pigment in leaves), which is important in carbohydrate production and it is required for certain enzyme functions. In high alkaline soils, iron is often unavailable to the plant which is why plants will often develop yellow leaves or look anemic. The University of Florida recommends adding chelated iron to the root area of the fruit tree when soils are above 7.0. Chelated iron is basically a type of iron with a special coating on it which will make it more available to the plant when the soil is alkaline. Many of our areas, especially along the coastal parts of Nassau, will have high alkaline soils. Fruit trees, such as your peach tree, could benefit from incorporating chelated iron into the soil around the roots. The directions on the package of chelated iron will provide the appropriate amount to apply. Please follow the directions on the package as too much chelated iron can cause other problems. Remember, you can always use less than the label recommendations but NEVER more. The “Label is the Law.”
Q: Can you tell me something about Pineapple pears? I have spots on the leaves, is that a problem?
A: Pears are great trees for the horticulturally-challenged. They tolerate many different soil conditions, don't require much care or fertilizing once established, rarely need pruning, and can produce bumper crops of fruit for decades, with little care. They can get a bacterial disease called "fire blight" in our area, where the tips of the branches whither and turn black.The pear's success also has a lot to do with its easy picking and easy storage. "Because pears are one of the few fruits that actually ripen more successfully off the tree," says Hazen, "they are picked when green and hard." It's true. Last year, I was almost buried by my pears, and had to keep them in bushels in my house until my friends came back from vacation. A week or so in my kitchen made the pears wonderful eating. The old-timers in Galveston County often pick the pears when they're "softball" hard, wrap each pear in newspaper, put them in a box, and store them in a cool dark place. Some varieties can keep for several months this way, but some can't. I found those left on the tree to ripen just became rotten.
Q: When should I prune my mature pear tree?
A: Mature apple and pear trees should not be pruned severely. Moderate annual pruning is preferred to heavy pruning every 3 or 4 years. Heavy pruning causes less flowering and excessive vegetative growth which can promote fire blight. Pruning should be done during dormant season which is usually late winter or early spring. For those of us in eastern part of North Florida that would mean February or March. For those with young pear trees we should encourage a modified central leader. A leader is one main limb we select to be the central leader. It is usually the most straight and middle upright branch. We want to develop and encourage scaffolding branches or those branches that grow laterally off the main branch. These scaffolding branches should never be taller than the main central leader. Fruit trees are generally not pruned the same way as our structural trees (live oaks) nor do they have the same life expectancy. We prune fruit trees for the purpose of producing more fruit. Certain pear varieties are self-fruitful; that is, they can pollinate themselves. Thus, if you want only one pear tree, a self-pollinating variety should be selected. Orient or Baldwin pear varieties are at least partially self-fruitful. Other pear varieties require cross-pollination. If you plant varieties that require cross-pollination, be sure to plant varieties that bloom at the same time. For instance you could plant Hood, Flordahome or Baldwin varieties together. For clear information on pruning fruit trees check out Clemson University’s publication:
Q: My Hood pear blooms and looks beautiful but it never produces any fruit. What is wrong?
A: Hood pears are a good choice for Northeast Florida but this pear will need a pollinator. I recommend you use Baldwin as it pollinates any of those pears requiring pollination. Other varieties which can be planted in our area are Flordahome, Hood, and Pineapple which are all early fruit producers. Baldwin, Cames, Kieffer, Orient, and Tenn, which are late fruit producers, are also suitable for North Florida. Apply one pound of fertilizer annually for each year of age of the tree until it reaches ten years of age. Divide the annual fertilizer in half and apply once in January and again in June. Use 8-8-8 or 6-6-6 and broadcast it completely under the canopy of the tree. Be sure to water it in slightly to the roots will have access to it. Keep lawn grass as far away from the trees as possible. Planting pears from seed is risky as they will not necessarily have the same characteristics of the parent plant. It is better to purchase a pear grafted onto a reliable rootstock. Pears will ripen as they age but pick them just before ripening and store at room temperature. http://dixie.ifas.ufl.edu/pdfs/gardening/pear.pdf
Q: When do I fertilize my adult pecan trees and how
A: For bearing trees, 2 to 4 pounds of fertilizer should be applied per inch of trunk diameter in February and again in June. If possible, use a fertilizer especially made for pecans – look for zinc on the label or use 10-10-10. Zinc deficiencies often cause leaves to bronze and crinkle. Some growers prefer to bury fertilizer at 10 or more sites below the tree canopy to reduce runoff and increase fertilizer use efficiency compared to a broadcast application. Large trees (30 inches or more in diameter) may require 60 to 120 pounds of fertilizer in February and again in June.
Q: I just moved into a house which has pecans growing in the yard. How do I take care of them – they seem to have been neglected.
A: We would suggest you start by having the soil tested to determine any nutrient imbalances. The Extension Office will have soil test kits and an overall nutrient test will only cost $7. Once you get the test back from the University of Florida, please give me a call and I can go over the analysis with you. Mature pecan trees can be heavy users of water and nutrients. Regarding the appropriate nutrients, when possible, homeowners should purchase fertilizers specifically formulated for pecans as they will contain minor elements necessary for best fruit formation. Zinc is often unavailable to pecans if the soil pH is over 6.0 but it is a common additive in pecan fertilizers. The symptom of zinc deficiency is crinkling of the leaves and small leaf size. Fertilization should be done in February and June with large trees measuring over 2 feet in diameter needing 60-120 pounds of fertilizer at each session. Irrigate about ¼ inch of water immediately after applying fertilizer to allow nutrients to reach absorbing root structures. One other important thing to know about pecans – they often are alternate bearing which means they produce pecans heavily one year and the next year will not bear as heavily. February is also the month to prune any dead, diseased or broken limbs. Pecan trees have very weak limb attachments so do not allow heavy infestations of Spanish moss to grow along the limbs. Spanish moss can be mechanically removed any time of year. If you want to grow your own pecans, choose ‘Cape Fear’, ‘Elliott’ or ‘Moreland’. Attached is a UF/IFAS publication on pecans: http://edis.ifas.ufl.edu/hs229
Q: What pecan varieties should I plant in the Northeast part of Florida?
A: The University of Florida has done extensive research on pecan varieties and the highest recommendations for Northeast Florida are for ‘Moreland’, ‘Cape Fear’ and ‘Elliot’. These three varieties have the best pest resistance and nut yield. Next in line for recommendation would be ‘Curtis’ and ‘Sumner’. Pecan trees are notoriously weak limbed trees but the three highly recommended trees (‘Moreland’, ‘Cape Fear’ and ‘Elliot’) are strong wood trees and all three reach maturity early. The strong tree characteristic makes these pecan trees less likely to experience branch breakage. Trees should be planted in the dormant season which would mean January or February. Soil pH should be between 5.5 and 6.5. If the soil is too acidic the trees may show deficiencies in zinc and manganese. Use dolomite lime to lower the pH if a soil test indicates acidic soil conditions. A complete fertilizer (10-10-10) should be applied during March and June for young trees and February and June for established trees. Complete information on planting and maintenance each of the pecan cultivars for our area is contained in the following UF/IFAS publication: http://edis.ifas.ufl.edu/HS229 and http://edis.ifas.ufl.edu/HS106
Q: Should I top my pecan tree? I recently saw pecan trees which were very lush and bushy but they had been topped.
A: I always love an opportunity to share proper pruning techniques with the public. These proper techniques have been proven the best for the tree through research provided by the Environmental Horticulture Department at the UF/IFAS. I am going to glean a portion of the UF/IFAS publication, “The Pecan” by Dr. Crocker and Dr. Anderson regarding proper pruning of pecans. “Trees at planting are normally a whip without branches. A newly planted tree should have between ½ and 1/3 of the top removed so as to bring roots and shoots into balance. (But this is the only time the tops are removed). Some terminology is in order. Tree training is performed early in the life of the tree to form a proper tree framework. Pecan trees should be trained to a central leader training system. Select a vigorous upright shoot as your main leader and remove adjacent shoots. This is very important. For commercial plantings, lateral branches should not be allowed to form from the newly established central leader until a height of 5 feet is achieved. Lateral branches must be at least five feet from the ground to avoid their interfering with cultural practices such as herbicide spraying and mechanical harvesting. Lateral limbs will become scaffold limbs as the tree matures. Ideally, lateral branches should be selected about every 18 inches in vertical height and positioned in all quadrants of the tree. To allow the accumulation of photosynthate, laterals that develop below a height of 5 feet can be retained temporarily for a year or two, but then they should be pruned off. Sprouts emanating from the rootstock (below the graft union) should be removed as they form. Pruning as little as necessary during the first several years will hasten tree development. Mature pecan trees are not routinely pruned.”
Q: When do I fertilize my persimmons?
A: Fertilizer requirements for persimmon trees are largely unknown for Florida conditions, but in general the persimmon needs less than citrus or peaches and in fact is thought to drop fruit if grown too vigorously. A balanced fertilizer such as a 10-10-10 or similar mixture is suggested at rates of ½ - 1 pound per year of age up to a maximum of 8 to 10 pounds on old trees. In the first year that the tree is planted, fertilizer should not be applied until April or May. Then approximately ½ - 1 pound of the 10-10-10 should be applied. Every year thereafter ½ of the fertilizer application should be made in January and the other half at the beginning of the rainy season in June. The fertilizer should be broadcast evenly beneath the tree, so avoid using the spiked type of fertilizers.
Q: What is wrong with my persimmon? Many of the leaves have browning around the edges. After talking to you, I went out and removed some of the stems and found a dark, discolored ring you suspected I might find. My friend thinks it is Botryosphaeria.
A: Thanks for sharing this info with me and after looking at the information on Botryosphaeria, I would agree with your friend. It is always nice to have someone this smart in your corner! Botryosphaeria dothideais a fungal disease and it is difficult to control in fruit crops. You may start to see cankers in the tree limbs and trunk, dieback on the outer limbs, stunted growth and oozing from the trunk tissue. The tree may live several years longer and still produce fruit but ultimately it will continue to spiral in decline and fruit production will also be reduced. The decline of the tree may make it more attractive to borers too. Fertilize using 6-6-6 or 8-8-8 and avoid high nitrogen products as they have a tendency to cause fruit drop. Keep the tree irrigated on a consistent basis but do not over water. Remember to keep lawn grass as far away from the tree as possible and lightly mulch 2-3 inches deep but 1-2 feet away from the trunk. Fuyu, which is the tree you have, is the recommended cultivar for Northeast Florida. Sometimes we can do all the right things and still the plant is not healthy and successful – don’t be too hard on yourself.
Q: What are some varieties of persimmon that can be grown here and what does non-stringent persimmon mean?
A: Oriental persimmons Diospyros kaki L., have been grown in Florida for many years. Some non-astringent varieties are Izu, Fuyu, Jiro. Common astringent varieties are Wase, Tanenashi, Eureka and Ormond. Astringent fruit often causes us to have a “mouth-puckering” response – usually very unpleasant for all mammals. Astringent persimmon fruit must be soft or artificially treated before astringency is removed and they are suitable for eating. Fruit of the non-astringent types lose astringency while still hard and can be eaten hard or soft. Choosing the proper harvest season for non-astringent persimmons is less complicated than for the astringent types, because they can be eaten firm. Non-astringent fruit are good for fresh eating and are excellent with pears, dates, apples, citrus, raisins, and/or coconut in salads. They have distinct advantages in marketing and handling because they can be picked earlier and have a longer shelf life. Consumer acceptance is greater because they do not have to be eaten in the "gooey-drippy" state which is objectionable to many people. Most of the persimmons have some form of Asian name in them and the meaning of the oriental words used have the following meanings: Kaki or Gaki - persimmon, Wase - early, Hana - flower of, Tanenashi - without seed, Fuyu - winter, Saijo - best, Gosho - imperial palace, Ichi - number one, and Ki - life. For more information check out the University of Florida publication, http://edis.ifas.ufl.edu/fy1115
Q: I have a pignut hickory tree and it produces loads of nuts. Can we eat them?
A: According to the Florida Division of Forestry, the fruit of the Pignut hickory, Carya glabra, can be eaten. But, always be sure any plant is properly identified before ingesting any part of it – fruit or leaves. There use to be an old wives tale which stated, “if birds eat it, it is safe for us to eat.” Do not use other animal’s ability to tolerate plant material to determine if the plant is safe to eat. Most accounts say the fruit is sweet. It is in the walnut family and found in most forests east of the Mississippi and even out to the west coast. This group of trees includes walnuts and pecans; it tolerates most any type of soil, or light condition. http://edis.ifas.ufl.edu/st121
Q: I believe we have two pineapple guavas
by our front door and one is losing its leaves dramatically. There
is a “beige colored” hard cocoon about 1.5“on
a branch. Also, this bush was bothered by the large multicolored
grasshoppers this summer and I suspect they did some damage. Any
help you can offer would be appreciated. We are transplants
A: Welcome to
Q: What is the white blooming tree I see just outside the wooded areas here? I know it is not a dogwood as the flowers are too small.
A: I believe you may be talking about the native flatwoods plum, Prunus umbellate. It is a round-topped, deciduous tree, reaching 20 feet in height with a 15-foot spread, which is most often planted for its spectacular display of blooms. Flatwoods plum trees are small trees produce a white, billowy, almost cloud-like appearance when they are clothed in the profuse, small, white flower clusters. These white, half-inch blooms are followed by one-inch-long, edible, purple fruits which vary in flavor from very tart to sweet. These small plums are an important and attractive food source to various forms of wildlife – mostly birds but yes even the occasional, annoying squirrel. They are perfect for cold hardiness zones 8-9 which includes most of Nassau County. Flatwoods plums grow well in full sun to part shade; they tolerate most any type of soil as long as it is well drained. This would be a perfect patio tree just be sure it is out of the area where it would receive the same irrigation as lawns, which would be too much water. Flatwoods plums cannot tolerate salt, even from ocean breezes so keep it away from the direct coastline. It has no major diseases and only occasionally my house tent caterpillars which can easily be hand removed. Flatwoods plums are easy care trees which also require very little pruning to be a beautiful upright tree. It is definitely an underutilized small tree. We have one in the main demonstration garden (James S. Page Governmental Complex) if you want to see it now (March) in full bloom. The attached publication is from the University of Florida: http://edis.ifas.ufl.edu/st521
Q: I would like to plant some plums in my yard but I am not sure which ones to buy.
A: The names of all University of Florida plum cultivars begin with the prefix 'Gulf.' These cultivars are Japanese type plums (Prunus salicina Lindl.) and have resistance to plum leaf scald (Xylella fastidiosa) and bacterial spot (Xanthomonas campestris). Fruit size is about 1½ to 2 in. diameter and fruit quality is good. They ripen in early to late May. 'Gulfbeauty' was released in 1998 and patented by the University of Florida which is the tree we have in the demonstration garden in Yulee. Fruit color is dark reddish purple and the flesh is yellow with a green hue. The skin is sour, which is common in Japanese plums, but the flesh is sweet, sub-acid and firm when ripe enough to eat. The flesh clings to the stone even when soft ripe. 'Gulfblaze' was released and patented by the UF and provides a mid-season plum. Fruit are very firm, medium-large, round and semi-freestone which means it is a little easier to pull the flesh from the stone pit. Fruit color is dark red to purple and the flesh is orange, sweet and sub-acid. Other plum choices are ‘Gulfrose’, ‘Gulfruby’ and ‘Gulfgold’. Plums fruit better when planted with more than one type of tree so consider purchasing two or more different types for cross-pollination. However, if you have a wild plum nearby, the bees will use it for cross-pollination. There are also some cultivars developed by Auburn University which would work well in our area too and those trees have Au in the front of the name, such as ‘Au-Rosa’ or ‘Au-Rubrum’. For more complete information check out the University of Florida publication: http://edis.ifas.ufl.edu/hs250
Q: What is wrong with my plums?
A: Your plums are showing the early stages of brown rot, which is caused by a fungus called Monilina fructicola. Brown rot can attack blooms, fruit, leaves, and stems. It over-winters on blighted stems and mummified fruit. Brown rot can be a problem during wet weather. I know what you are thinking – we have had very little rain but remember the spores have been there all along and they are just now causing issues with the fruit. In addition, we create an artificial environment by applying irrigation to the trees – sometimes twice a week. It is best to irrigate any tree and shrub at the root keeping the water off the leaves. Infections will appear as masses of brown to brown gray spores on infected tissue if left on the tree long enough. It is important to prune the tree in an open vase-shape to encourage good air flow which reduces the spore problem. At this point, we have no plum cultivars resistant to brown rot, and fungicide sprays may be necessary during wet weather or irrigation landscapes. The best time to apply fungicide is just at the new leaves are forming, just after flower budding and fruit setting. Use a fungal spray specifically developed for fruit tree species. It is also very important to remove any fruit from the tree and not allow it to go from one season to the next. Clean away any leaf, stem and fruit debris from around the base of the tree as these can be the source of the fungal spores, creating the perfect environment for future spore dispersal to the tree.
Q: I purchased some plums and I now I wonder if I made the best choice.
A: When purchasing fruit, or any plant, it is best to determine if theses plants are varieties well suited for our area. The plums you selected perform well in the California area but they are not the best choices for Florida. We would suggest selecting a cultivar with the prefix “Gulf” in front of it such as ‘Gulfbeauty’, ‘Gulfruby’, ‘Gulfblaze’ or ‘Gulfrose’. These are Japanese plum varieties which are more disease resistant and require fewer chilling hours or cold days to develop fruit. The peel is slightly bitter but the fruit is sweet on these varieties and they all ripen in early May. The two trees you have purchased, ‘Methley’ and ‘Santa Rosa’, are older varieties which are no longer recommended for our area. Both of these are susceptible to plum leaf scald and several bacterial diseases and the fruit quality is not high. Use a general fertilizer such as 6-6-6 or 8-8-8. Remember the numbers represent Nitrogen, Phosphorus, and Potassium. Consistent irrigation, especially during fruiting and flowering season, is important for best fruit production. Learning appropriate pruning techniques is also essential. The publication from the University of Florida, “Growing Plums in Florida”, provides more information about fertilizing, pruning and watering. http://edis.ifas.ufl.edu/pdffiles/HS/HS25000.pdf
Q: I tasted pomegranate fruit for the first time this year and I love it. Now I am seeing the fruit is in abundance in all the grocery stores. Can we grow it in Northeast Florida?
A: Pomegranates are typically grown in warm temperate climates with the ideal conditions receiving cool winters and hot, dry summers. Pomegranates are native to southeastern Europe and Asia and were grown in ancient Egypt, Babylon, India, and Iran. These fruits were also grown extensively in Spain, moved with missionaries into Mexico and California in the 16th century. It is possible for us to grow pomegranates and the Extension office has a small tree in the Yulee demonstration garden now. Our tree produced 2 small fruit this first year. I am willing to try the fruit, because, like you, I think they are delicious. Not only is the fruit wonderful, the tree produces a beautiful orange flower in the late summer and early autumn. California has the most ideal climate for heavy production – the softball size pomegranates you see at the markets. We do not have to worry too much about cold damage here and the pomegranate can tolerate temperatures as low as ten degrees which makes it much less sensitive than citrus. It would make an excellent small tree for smaller yards as it grows between 12 and 20 feet tall. It should be planted where it can receive sufficient, full time, sunlight. Consider choosing ‘Purple Seed’ or ‘Spanish Ruby’ as your choice for planting in your yard. Soil should be slightly organic with a pH of 5.5 to 7.0. Fertilize in March and November using a complete fertilizer such as 8-8-8. Over fertilization and over watering can cause fruit drop – remember balance in everything! For more complete information, read the University of Florida publication on pomegranates. http://edis.ifas.ufl.edu/pdffiles/MG/MG05600.pdf
Q: I am interested in growing pummelos. What can you tell me about them?
A: Pummelo, Citrus maxima, looks similar to a grapefruit but quite different. It is a very large, round to pear-shaped, yellowish orange fruit with very thick rind. The fruit is so large there have been records of fruit weighing up to 20 pounds; however each fruit is more typically around 5 pounds. Still, it is a large single fruit to hang from a tree by anyone’s standards. Although it looks similar to a grapefruit the flesh is sweeter and less bitter. Because of the size of the fruit and the thick rind it is generally not a consumer favorite. Thus, you many have some difficulty finding it in local grocery markets or plant nurseries. Once the thick rind is removed the flesh divides easily into separate sections. Although it is important to also note the sections may differ in size and form on some of the pummelo cultivars. The tree can grow to heights of 30 feet with an equally wide spread so consider its mature size when planting it in the landscape. Pummelo is typically grown in cold hardiness zone 9-11. When planting in the landscape provide as much sun exposure as possible but avoid areas where wind could be an issue. Some of the more common varieties of pummelo include: Chandler, Ichang, Red Shaddock, Reinking, and Webber. There are three new cultivars of pummelo which have been released to Florida citrus growers which means we should see them at the market. One other important thing to know about pummelo – UF is working on producing a hybrid with grapefruit which will give you the peppery tang of the grapefruit but avoid the serious drug interaction problems typically caused by grapefruit. The professor’s findings have been reported in the October 2011 issue of the Journal of the American Society for Horticultural Science.
Q. Is it possible to grow red raspberries in North Florida? If so, what varieties? RW
A. According to the University of Florida, raspberries are difficult to grow here as perennials and the flavor of the berries is fair to poor. Raspberries are typically grown in the north so I do not want you to be discouraged if yours do not do well. It is not you, it is the plant. Here is an section from one of our publications: . 'Dorman Red' is the only raspberry cultivar recommended for trial in Florida when grown as a perennial crop; however, berry flavor is poor to fair. 'Heritage' raspberry has been grown as an annual crop during the winter in the southern parts of the state after it receives its chilling requirement. I have attached the complete publication for your perusal. http://edis.ifas.ufl.edu/hs104
I have also included a publication from North Carolina which is about growing raspberries in the home garden: http://www.ces.ncsu.edu/depts/hort/hil/hil-8204.html
Q: When should I plant strawberries here in Northeast Florida?
A: Plant strawberries in late October through November. Place strawberry plants in rows 36 inches apart and 12 inches apart within each row. Elevate rows 6” above existing soil to ensure good drainage, whenever possible, use drip irrigation to reduce disease on leaves and fruit. Use pine straw to reduce weed problems and slugs. Specific cultivars recommended by the University of Florida are: ‘Strawberry Festival’ (plant October 10-20); ‘Florida Radiance’ (plant October 5-15); ‘Winterstar’ (plant October 1-5). Check out the University of Florida publications on strawberries: Growing strawberries for the Home Garden:http://edis.ifas.ufl.edu/pdffiles/HS/HS40300.pdf
Q: I know it is the end of the watermelon season but we just bought a seedless one. Do watermelons ripen after they are picked?
A: Once a watermelon is removed from the vine, it will no longer be able to become sweeter. Other fruit such as some citrus, grapes, cherries, blackberries, and strawberries do not ripen or sweeten further after they are picked. So be sure you pick the best and eat them soon after selection. However, some fruit will ripen after picking and a few examples of those are bananas, avocados, fig, apples, peaches, pears and plums. Seedless watermelons are sterile hybrids which develop fruits, but no seeds. The seeds for growing them are produced by crossing a normal watermelon with one changed genetically by treatment with a chemical called colchicine. The seeds from this cross will produce plants that, when pollinated with pollen from normal plants, produce seedless melons. Attached is a short publication on seedless watermelon from the University of Florida: http://edis.ifas.ufl.edu/mv152