Q: What is wrong with my lawn grass?
A: I have seen dozens of grass specimens over the last 2 weeks – all of these had root decays and leaf spots on them caused by fungi. Many of these diseases have been caused by a combination of the fungi and too much water. The fungi are naturally occurring in the soil and healthy grass does not fall prey to the disease except under perfect conditions. Although there is little we can do about the rain, but we should not contribute to the problem by leaving our irrigation systems on. Please consider turning the irrigation system onto manual. I know it is hard to believe too much water can cause these kinds of problems but truly there is no other reason for root decay except too much water and/or poorly drained soil. Then, if we combine too much water with too much nitrogen, the two can certainly become deadly for the grass. Just a few other things: water grass in the early morning (4am – 10am); mow grass on highest height, and keep mower blades sharp. Normally, we would tell you not bag your grass clippings, but if a disease is present on the grass blades, it is best to bag them and throw them away.
Q: I have small to large areas of my St. Augustine lawn which have yellowing blades. They can easily be pulled up and seem to be rotting. Some of the edges look like circles. The smaller areas are about a foot across while other areas are much larger – almost 10 feet wide. What could be the cause? CN
A: I believe you most likely have a fungal growth called large patch or brown patch, which is commonly found in St. Augustinegrass. The fungal agent is called Rhizoctonia solani. This disease is most likely to be observed from November through May when temperatures are below 80°F. It is normally not observed in the summer. Infection is triggered by rainfall, excessive irrigation, or extended periods of high humidity resulting in the leaves being continuously wet for 48 hours or more. This disease usually begins as small patches (about 1 ft. in diameter) that turn yellow and then reddish brown, brown, or straw colored as the leaves start to die. Patches can expand to several feet in diameter. It is not uncommon to see rings of yellow or brown turf with apparently healthy turf in the center. Turf at the outer margin of a patch may appear dark and wilted. Avoid excess nitrogen during potential disease development periods. Limit readily available forms of nitrogen, such as soluble liquids or quick-release nitrogen sources, just prior to or during these periods. Instead, use slow-release nitrogen sources. Apply a balanced fertilizer containing equivalent amounts of potassium and nitrogen, preferably a slow-release potassium form. Irrigate only when necessary and do so only in the early morning hours when dew is already present. Since mowers can spread this disease, mow diseased areas last, and wash turf clippings off the mower before proceeding to the next site. Chemical controls are listed in the publication attached, be sure to follow the directions on the label and alternate the type of chemicals used. But nothing will change if the watering and fertilizing practices are not corrected. http://edis.ifas.ufl.edu/lh044
Q: You often talk about not overusing Nitrogen fertilizers but isn't it needed to keep the grass growing?
A: I am going to take a recent study and use parts of it to answer your question. Nitrogen is important for growth but we generally are using too much. A little fertilizer can perk up a St. Augustinegrass lawn as spring arrives, but homeowners who overdo it may find they're growing more than grass. A University of Florida study suggests repeatedly using large amounts of nitrogen fertilizer can ignite a population explosion of Southern chinch bugs – the No. 1 insect pest of St. Augustinegrass, the state's most popular turfgrass. "Everything in moderation," said Eileen Buss, an associate professor of entomology with UF's Institute of Food and Agricultural Sciences. "When we try to overly manage a natural system we get the balance out of whack." UF turfgrass experts advise homeowners to use no more than 1 pound of slow-release nitrogen fertilizer per 1,000 square feet of lawn, a recommendation found in the document "St. Augustinegrass for Florida Lawns," available at http://edis.ifas.ufl.edu/LH010. In the study, Southern chinch bugs produced the most eggs on St. Augustinegrass fed the equivalent of 2 pounds nitrogen per 1,000 square feet per month. That rate is a worst-case scenario, Buss said, but not unrealistic because people sometimes deliberately overfertilize in their zest to have the greenest lawn in the neighborhood. Resistant chinch bugs may be able to survive exposure to bifenthrin, a pyrethroid which is the top choice for Southern chinch bug control in Florida. However, pyrethroids should still perform well against nonresistant populations of Southern chinch bugs. Future research may examine the role of the nutrients phosphorus and potassium in chinch bug population growth, and the possibility of overfertilization may reduce turfgrass resistance to chinch bugs. Use 15-0-15 starting in April and use is in small increments until September so the plant can absorb it and grow slowly.
Q: I know the numbers on the fertilizer bag represent the amount of nitrogen, phosphate, and potassium contained in the fertilizer, but how do these nutrients help my plants?
A: This is a good question because many of us use fertilizer quite often. It is common to assume everyone knows what the essential elements are and why they are needed – so thank you for asking. The numbers on the fertilizer bag do represent the elements you listed nitrogen (N), phosphorus (P), and potassium (K) which are all important for normal plant and animal processes such as growth, reproduction and protection. In the most general of terms nitrogen is necessary for growth and production of new leaves. Phosphorus is vital for production of flowers and fruit. Potassium assists the plant build root structures and enables it to withstand harsh stresses such as heat, cold and drought. It is good to remember fertilizers are not food but rather it assists the plant with the normal system functions of reproduction, growth and survival. Leaves are the food factories of the plant. Fertilizers may not need to be applied every spring and fall or even every year if the plants are healthy and established, which is especially true of mature trees. Do not apply fertilizer when the tree is fruiting or flowering as this may cause the flowers and fruit to drop. If plants are consistently showing signs of nutrient deficiencies it may be best to move them to a more appropriate site. Fertilizer should not be applied during times of drought unless supplemental irrigation can be supplied. Nor should fertilizer be applied when storms are imminent as the fertilizer will end up in storm water drains rather than its intended target. I always found the process of adding nitrogen to shrubs a curious activity. The added nitrogen increases the plant’s leaf and stem production which causes someone to prune the new growth off a few weeks later. It seems counter-productive – yes, a curious activity indeed.
Q: I looked at the FDACS fertilizer publication you put in the newspaper a few weeks ago. Does this really mean we will no longer able to use fertilizer products such as “weed and feed”, “lawn grass winterizer”, and “lawn grass turfbuilder” on our lawn grass?
A: Because of the problems with algae blooms in our rivers, streams and ponds throughout Florida this law has come into fruition. This means after July 2009, the products you mentioned will no longer be sold here if they contain high nitrogen and phosphorus. It will be legal to sell anything currently on the shelves until the inventory is gone. We are all deeply concerned about having safe and sufficient amounts of drinking water. With demands for water increasing, the Legislature took steps to ensure water is protected for current and future use. For years, the green industry, growers, farmers, forestry and landscape professionals have been complying with Best Management Practice (BMP) recommendations from the Environmental Protection Agency (EPA) and yet we continue to have waterways polluted. The next step is to reduce the amount of nitrogen and phosphorus leaching into water via non-point sources such as home landscapes. One way to do this is to agree to fertilize lawns and landscapes properly. This should not reduce the quality of the lawns, in fact, we are confident it will benefit the lawns by reducing the amount of disease and insect damage especially when combined with proper irrigation. For too long, we have been producing lush, dark green home lawns which are the prefect environment for disease and insects. We receive hundreds of phone calls and office visits annually from people concerned about why their lawns are in decline. Invariably, we find the grass is receiving too much nitrogen, too much water and/or being mowed too short. We will be conducting a BMP class for landscape professionals on Friday, March 27 at the Yulee County Building. The cost is $25 per person and CEUs will be available. Contact me, Rebecca Jordi, at 548-1116 or firstname.lastname@example.org for more information. Duval County currently requires anyone who professionally applies fertilizers to commercial or home landscapes to be BMP certified. We would encourage all of you ask if your landscape professionals are currently certified in BMPs. It will benefit the environment and the landscapes.
Q: I want to do the right thing regarding the new fertilizer ordinance but I am concerned about not using any phosphorus on the lawn. How do I know if the lawn is deficient?
A: Nutrient deficiencies seldom occur alone and these deficiencies in plant material often look similar. It is therefore difficult to determine exactly which nutrient is lacking simply by looking at the grass blades or plant leaf. Some studies on forage (lawn grass cousins) grasses and agriculture crops have indicated the blades may lose their green color because of the breakdown of chlorophyll in the blades. The other color pigments such as anthocyanins (red, purple, or blue) will no longer be masked and the leaves may develop purple edging or streaks. However, this same coloration may occur when the grass blades are exposed to cooler temperatures. Phosphorus is important in cell division and elongation of cells, therefore the blades may be somewhat stunted but not many people complain about not having to mow as often. So, how do we know if a phosphorus deficiency has occurred? A soil test would help you determine if the soil is lacking in phosphorus which would enable you to add phosphorus (according to the fertilizer label) to the lawn. You would need to send the soil to a reputable laboratory for analysis. The University of Florida Soils Lab will charge only $7 for such a test. It will take about ten to fourteen days to receive the report back, which would be a worthwhile investment for you. Contact your local County Extension Office for information of obtaining a soil test kit. Attached is the FDACS publication on urban turf fertilizers: http://www.flaes.org/pdf/Urban_turf_fact_sheet.pdf Mississippi State University photo of phosphate deficiency on corn
Q: We are going to try to maintain our yard ourselves this year. I purchased 15-0-15, applied it and then realized it said it was for centipede grass. Will this be okay? Also we have a lot of weed that reminds me of strawberry plants. What do we do with this? Thanks for any input you can give us.
A: You may use the fertilizer 15-0-15. In fact, I have seen this product and it has a large amount of the nitrogen, about 50%, which is slow release. This slow release nitrogen will provide some nitrogen for the plant to absorb a few weeks after the quick release nitrogen has been absorbed by the grass. The University of Florida suggests you fertilize in March and again in August or September. Apply an iron sulfate product during the summer and be sure it contains very little nitrogen. The weed you described may be Indian Mock strawberry or Oldfield Cinquefoil. Either way it is a perennial broadleaf weed and you can use a broadleaf weed killer on it as long as the product can be used on your St. Augustine grass. Be sure to read the directions carefully and completely before applying it to your lawn. We would also suggest you apply it only where you have the weed problem (called spot treating) rather than spreading it all over the lawn. Take care of the lawn properly and it will give you years of pleasure.
Q: I have St. Augustine grass and I put out a complete fertilizer of 16-4-8 like you suggested but should I use a “winterizer” this month? I am so tempted because so many of my neighbors are using it.
A: People are going to think I paid you to ask that question. The immediate answer is no fertilizer should be applied to turfgrass in October. In fact, the University of Florida suggests allowing turfgrass to go dormant from October through February. When we discussed fertilizer we talked about being sure it contained some slow release nitrogen. The product you purchased has about 6.5% slow release nitrogen, which is good. The only way to know what percentage of the nitrogen in the bag is slow release is to examine the label. Generally you will see an asterisk by the nitrogen number, which is always listed first on the label. Exam the label for the asterisk and the label will use words like “water insoluble nitrogen” or “poly-coated nitrogen”. Since you applied the fertilizer to your lawn in September the slow release nitrogen will be available for the grass to absorb this month. Apply a complete fertilizer again in March such as 16-4-8 or 15-0-15, but be sure it has slow release nitrogen in it too. All you need to do for the next 5 months is occasionally mow the grass and water it once every 10-14 days. Since you don’t need to mow as often you might take your mower blades to a shop to have them sharpened. This is the time of year you can focus on things other than your lawn such as the holidays or visiting family. You can breathe a sigh of relief now!
Q: Should I use fertilizer spikes or the granular stuff found in bags?
A: Broadcast fertilizers work best on trees and shrubs as they feed the whole root area. The disadvantage of fertilizer spikes is they only get to the roots immediately surrounding the spike. If you currently have fertilizer spikes, simply crumble them and spread them under the canopy of the tree or shrub. Gently remove any mulch prior to spreading, especially if you are have cypress mulch, which has a tendency to become compacted. Spread the fertilizer from just outside the trunk of the tree, shrub or palm throughout the whole area underneath the canopy. Water in the fertilizer then replace the mulch. Adult trees and shrubs, which have been in the landscape for three years or more, need not be fertilized especially if they are growing near lawngrass areas. Remember that fertilizer is not food; the leaves of the plant supply the food for the plant. If the tree or shrub is growing well and appears to be healthy it is probably not necessary to apply fertilizer. Of course, there are exceptions to every rule and palms, citrus and flowering plants fit into that category. Palms are heavy users of potassium, magnesium, and manganese, therefore give them fertilizers specially formulated for palms three to six times a year. Look for a palm fertilizer with a nutrient ratio as close to 2:1:3:1 (Nitrogen:Phosphorus:K-Potassium:Mg-Magnesium, respectively) as possible. Try to find a fertilizer where the N, K, and Mg are in a controlled or slow-release form. The nutrients will probably be sulfur-coated or resin-coated in order to make them slow release. So look for a formula along the lines of 8:4:12:4, where the last “4" is magnesium. This will give you a great fertilizer that will keep your palms growing but with less chance of potassium or magnesium deficiencies developing. Citrus requires fertilization in small increments several times a year but avoid fertilizing from October through February. Acid loving plants such as azalea can be fertilized spring, summer and fall. Camellias can be fertilized before spring growth, after first flush, midsummer and early winter. Always, always, always (did I stress that enough?) follow the directions on the fertilizer label. Look for slow release nitrogen on all your fertilizer purchases.
Q:I’ve been told by one of the local retail garden centers to use 10-10-10 on my St. Augustinegrass lawn this summer.Your material says something different. What type is best?
A: I’m glad you asked this question especially when there seems to be so much information in the media and advertisements about lawn grass. I am attaching a publication from the University of Florida/IFAS regarding initial research on how to care for St. Augustinegrass. New research information is being released annually so what I am giving you is according to our most recent results. In a nutshell, UF recommends using fertilizers with compositions of 15-0-15 or 15-2-15. The numbers represent nitrogen (N), phosphorus (P) and potassium (K) respectively. In general, application of lawn grass fertilizers should occur March, May and September. During the summer, you might apply iron sulfate (Ironite) which will help turn the grass leaves green but avoid fertilizer products with large amounts of nitrogen. http://edis.ifas.ufl.edu/EP236
Q: I was considering replacing some of my lawn but I was told not to plant victory grass in its place. What can you tell me about victory grass?
A: I have not heard of victory grass but then I realized your friend might have been referring to the seed head of a type of bahiagrass called Pensacola. The seed head is “v-shape” hence the sign meaning victory. Pensacola bahiagrass got its name from the city Pensacola, Florida from where the grass was selected in 1935. There are several varieties of bahiagrass but it is commonly used along roadsides because of its ability to handle numerous stresses. This ability is the result of its deep root system. Pensacola is not the best choice of bahiagrass for home lawns as the v-shaped seed head is tough to mow and keep short when using a typical home mower. A better choice of bahiagrass for home lawns would be Argentine bahiagrass as it has a wider and darker green colored blade than Pensacola. Argentine bahiagrass is also disease and insect resistant and cold tolerant. Before selecting a grass for your home landscape consider having the soil tested to better determine which type of grass might be better suited for your area. Contact your local Extension Office for soil test kits and more information of different types of lawngrass. Check out the University of Florida website on residential lawn varieties for the most current information. http://hort.ufl.edu/yourfloridalawn/
Q: I have some bare spots in my bahiagrass. Can I reseed those areas?
A: Absolutely. Since this is your home lawn we would recommend you use Argentine Bahiagrass and April is the optimal month to put out seed. Be sure to lightly hand water those area to give the seeds a better chance to germinate. Purchase good quality seeds with a high chance of producing young seedlings. Try to get as high a percentage of bahiagrass seed only.
Q: I was thinking about seeding a small, sunny area of my lawn with Argentine bahiasgrass. My neighbor thinks it is a bad idea. What are your thoughts? DM
A: Argentine bahiagrass is a beautiful grass for home lawns and would be a good choice providing your soil pH is acidic enough. I have found most of the soil in our area is quite the opposite – most soils are alkaline. After testing your soil, it became obvious you should consider another grass as the soil pH measured at 7.45. Bahiagrass ideally would like the soil pH to be 5.5 so your soil is almost 100 times more alkaline than bahiagrass would prefer. This gives the grass a very poor starting point in addition to providing a permanent stress factor. While we might be able to adjust the pH on a temporary basis it will only be temporary. For your soil, the best choices for warm season grasses are Bermudagrass and St. Augustinegrass. It is difficult enough to grow grass here with normal stress factors such as heat, drought and cold. If the soil pH is too high or alkaline it will only compound your problems. One other thing, it is a misconception to assume your soil pH is acidic simply because oaks are growing in your yard and the leaves drop into the soil. It takes so long for them to decompose and alter soil pH. The only sure way to know the soil pH is to have it tested. We can do a test for you at no cost. Get a bucket; collect soil 4-6 inches deep from various areas within your lawn and drop it into the bucket. Mix the soil in the bucket and bring up a portion of the soil to one of our offices. The main office in Callahan is available most days from 8am – 5pm. The Yulee satellite office has a Master Gardener on duty from 10am – 2pm on Fridays only (if it is not a holiday).
Q: I am having some difficulty keeping my centipedegrass healthy. I have been using a common fertilizer found at any of the garden centers but a friend told me to call you because I might be over doing it. I fertilized in the late winter, then again in the spring and I am about to fertilize again. What should I use? I have also used a weed killer which contains the active ingredient 2,4-D.
A: Centipedegrass requires very little nitrogen therefore the fertilizer you are currently using is too high in nitrogen compared to the amount of potassium. We would recommend a configuration of 15-0-15. Remember the configuration is listed in the order of nitrogen first, phosphorus second and potassium last. It would be prudent to apply nitrogen in the formulation of nitrogen sulfate for centipedegrass as this grass prefers a more acid soil between 5.5 and 6.5. The sulfur compound in nitrogen sulfate will help lower the soil pH on a temporary basis which will enable centipedegrass to absorb the nutrients. Consider fertilizing centipedegrass only twice a year, spring and fall. Centipedegrass will never be as dark green as the standard St. Augustinegrass so do not try to over fertilize to produce the dark green color. It is possible a portion of the damage to your lawn may have been caused by the weed killer. Some herbicide labels containing 2,4-D indicates the product should not be used on certain cultivars of St. Augustinegrass or centipedegrass. Therefore, it is possible the damage on your lawn may have been caused by the combination of herbicide and the application of the high nitrogen from the fertilizer.
Q: I am thinking of seeding my yard with centipede grass seed. What should I know about this grass?
A: The first and most important thing to know is the soil pH. This grass likes an acid, infertile soil with pH around 5.0 to 5.5. Centipedegrass is a slow growing, low maintenance grass with low fertility requirements. It grows close to the ground, is medium-textured and is naturally pale green in color. Over fertilizing in order to produce a dark green color reduces its cold tolerance, increases long-term maintenance problems, and is believed to contribute to "centipedegrass decline." It has fair to good shade tolerance and good drought tolerance. It can be established from seed, sod, or plugs and spreads by stolons. For more specific information about centipedegrass check out the University of Florida website: http://edis.ifas.ufl.edu/ep288
Q: I would like to know where I can purchase fescue grass for this area.
A: The reason you have been having difficulty finding fescue grass at local garden centers is because fescue is a cool season grass and does not grow well in this area. Northeast Florida is far enough south to limit the type of lawn grass to only warm season grasses. Your choices are Bahia (Argentine), Bermuda (common), Centipede (if the soil pH is correct), St. Augustine (several cultivars), and Zoysia. The University of Florida has a web site specifically regarding the selection of residential lawn grass for our area. Each of the aforementioned grasses has a page with in depth information on warm season lawn grass varieties. The information will include proper planting, mowing height, irrigation needs, and fertilization. Take time to look at each of the advantages and disadvantages of the grasses to determine which might best suit your home lawn. It is advisable to have a full soil nutrient analysis done by the University of Florida ($7) prior to planting. You can pick up a soil sample kit at either Nassau County Extension site. The main Extension office is in Callahan, which is located at 543350 U. S. Highway #1 (on the Fairgrounds), 904 387-1019. The Yulee satellite office is at 86026 Pages Dairy Rd. (across from the old Yulee Middle School), 904 - 530-6350. The UF/IFAS website is: http://hort.ifas.ufl.edu/yourfloridalawn/
Q: I am considering replacing my lawn at the beach with Seashore paspalum grass. Where can I get it?
A: Dr. Laurie Trenholm is one of the turfgrass experts at the University of Florida. The website for complete information regarding home lawns is attached: http://hort.ifas.ufl.edu/yourfloridalawn/
I have also attached an older document on Seashore paspalum but the newest research from Dr. Trenholm is not yet available in this document. However, much of the care of Seashore paspalum is still accurate: http://www.tbwg.org/water/seashore%20paspalum.pdf You will probably have some difficulty locating this grass for the home landscape as we have had very little success with it becoming completely established here. The common mistakes made with St. Augustinegrass are often the same ones made with Seashore paspalum. Those mistakes are watering too often, using high nitrogen fertilizers and mowing the grass blades too short. Any combination of these cultural practices can cause the grass to decline. The best chance of obtaining Seashore paspalum would be through a local nursery, especially one which normally provides lawn grass to homeowners. Just a couple of other hints about lawn grass along coastal areas which may help you enjoy your landscape. Consider reducing the amount of lawn grass in the high salt and wind areas as they require too much attention to keep them in good health. Expand your bedding areas and increase the mulched spaces under trees. Choose an appropriate cultivar for shady areas as most lawn grasses love full sun and Seashore paspalum is one of those grasses. Trying to grow grass in shady sites produces poor plant material and then no one is happy with the results. Reduce the amount of water and fertilizer you apply to any grass grown in the shade.
Q: My St. Augustinegrass is pale and it does not look healthy. What could be wrong?
A: After talking to you about how to care for your lawn grass we realized the lawn was not being watered deeply enough. St. Augustinegrass should be watered about 1 inch each time, which is quite a lot of water. This grass responds well to watering deeply but less often (preferably once every 5 -7 days) or as needed. Once we discovered the pH of your soil was 7.5 (alkaline) it became evident that some of the nutrients were not available for the plant to absorb. St. Augustinegrass prefers the soil pH be around 6.5. It would be best to use slow release fertilizers that have the micro-element sulfur, which will temporarily lower the pH and help the plant’s ability to absorb the nutrients it needs. There is no quick fix for high pH soil which is why it is so important to never add lime to our Florida soils unless your soil had been tested.
Q: In my neighborhood I have noticed some lawns are already totally brown and dead while others are still green. All of the lawns are St. Augustinegrass so how do you account for the differences?
A: First, simply because the grass blade is brown, does not necessarily mean the grass is totally dead. It is important for the stolon, which is the above ground stem, and roots to be kept alive during the winter months. If the stolon is still green and the roots are healthy, your lawn should come back once the spring returns, which is usually March. We would recommend cutting back on watering during the cooler months to once every 10-14 days to ensure the roots receive ample water. Of course, cut back on irrigation it rains. Do not be tempted to keep the same watering schedule as during the growing spring and summer months because this can contribute to disease issues. Winter is also not the time of year to apply nitrogen to the lawn – allow your lawn to go dormant from October through February here in the Northeast part of Florida. I know some of you from colder climates are thinking this is not winter at all. Well, this grass is a warm season grass and as far as it is concerned – this is cold! There are many different cultivars of St. Augustinegrass – some are more tolerant to the cold than others which mean some may turn brown earlier than others. However, taking care of any St. Augustinegrass properly at all times of the year absolutely determines how well it is able to tolerate stresses such as drought or cold. If you are concerned about your grass, please call the Yulee satellite office (904 548-1116) for a grass “check-up” appointment. In a nutshell the following are the proper care instructions:
- Mow at the highest height for the cultivar
- Irrigate evenly (1/4 – ½ inch) from 6am to 10am, once every 3-7 days in the summer, once every 10-14 days in the winter, calibrate your irrigation system
- Use 15-0-15 slow release fertilizers March, May & September
- Avoid broadcasting insecticides, herbicides and fungicides annually but instead spot treat once a firm diagnosis has be given
- Call your local County Extension Agent for more specific information regarding appropriate care of lawngrass and specific fertilizer and irrigation ordinances.
Q: What is wrong with my St. Augustinegrass. I looked beautiful last year but I have had to replace portions of it for the last few years.
A: It was very helpful for you to bring in a section of the lawn to me, which included the soil, roots, stolen and blades. In your particular instance, you have been watering deeply but less often and this has created a good, deep root structure. However, I found fungal lesions on many of the root structures. This fungal damage reduces the ability of the roots to absorb sufficient amounts of water and nutrients from the soil. This will cause the blade (leaf) to wilt and appear to be suffering from lack of water. Adding more water only exacerbates the situation and the cycle of decline begins. In addition, many of the grass blades had gray leaf spot. This fungal disease loves warm, wet conditions, which often occurs during the months between May and September. Gray leaf spot can potentially kill large patches of St. Augustinegrass. Once those areas have died, they must be replaced. Certain cultivars (Classic, Seville, and Raleigh) of St. Augustinegrass appear to less susceptible to gray leaf spot therefore you might consider using one of them as a replacement. The St. Augustine grass used most often in Northeast Florida is standard Floratam which succumbs more readily to the disease. Fungicides need to be applied just prior to the peak rainy season for maximum protection. Local pesticide companies have chemicals homeowners are unable to obtain. However, products are available over the counter – please use them responsibly and follow the directions on the label. Irrigation is best applied in the morning hours of 6-10am to prevent the grass blades from being moist for extended periods. Avoid applying high nitrogen fertilizers to the lawn; instead use 15-0-15 slow release products. Attached is the University of Florida publication “Gray Leaf Spot of St. Augustinegrass: Cultural and Chemical Management Options”. http://edis.ifas.ufl.edu/PP126
Q: What is wrong with my St. Augustinegrass? It seems to be dying in large areas all around my yard.
A: I have received dozens of phone calls and office visits regarding this very question within the last two weeks. Because of all the rain we have been receiving, it would be best if we all placed our irrigation systems on manual. I have not needed to run my irrigation system in almost two months. I realize we are allowed to run our irrigation twice a week according to St. Johns River Water Management but it does not mean we must or should. Please look at the blades of grass and if they are flat and dark green then it is not necessary to run your irrigation. When the blades begin to slightly fold onto themselves, then it is time to irrigate. Part of the diagnosis process is examining the lawn grass therefore it was essential for you to submit a sample to me (12 inch by 12 inch) which includes the roots, stolon, blades and soil. After looking at your sample it was easy to determine one of the problems was grey leaf spot. If left untreated, it can destroy the lawn but your specimen also show root rot and decline. Once the roots of any plant are destroyed, it is nearly impossible for the plant to recover. In addition, we have no chemical able to correct this type of root damage to lawn grass. Our best method of control is prevention. How do we prevent this problem in the future? We must control the amount of water applied to the lawn. St. Augustinegrass prefers to be watered deeply but less often than we would assume. The root rot caused the blades to wilt. This reaction often makes us assume the grass needs more water so we turn on the sprinklers only to be causing the disease to spread even farther. What can you do now? Rake out any dead grass, reduce the amount of water used, do not apply high nitrogen in the summer and avoid using weed killers in the high temperatures.
Q: I need some other choices of St. Augustinegrass for a more shaded site.
A: Shade tolerant lawn grass needs about 4 hours of sunlight to perform properly. If you do not feel your site has sufficient sunlight consider some alternative ground covers such as Asiatic jasmine, mondo grass, liriope or Aztec grass. If you wish to try one of the more shade tolerant St. Augustinegrass varieties, then consider using ‘Delmar’ or ‘Seville’. 'Delmar' is considered a dwarf variety and should be mowed at a height of 1.5 to 2.5 inches. ‘Seville’ is also a dwarf variety which has finer leaf blades, grows a little taller than 'Delmar' and therefore it should be mowed at 2 to 2.5 inches in height. ‘Seville’ is not as cold tolerant and with the results of our last few winters it might not be the best choice here except along the coastal areas. Both have the same disease and insect issues as other St. Augustinegrasses especially if over- watered and/or over-fertilized with high nitrogen. Attached is a complete publication from the University of Florida regarding care, maintenance and selection of St. Augustinegrass. http://edis.ifas.ufl.edu/pdffiles/LH/LH01000.pdf
Q: Most of my St. Augustine lawn looks dead but some areas have some green patches still showing especially near my house and under my trees. How will I know if my grass is completely dead? Will I have to replace all of it? A: It is still too early to tell what part of our lawns will recover. Temperatures this winter were in the teens in most of our area on numerous occasions this winter. Therefore, I suspect a large percentage of our lawns will show at least some freeze damage. Because of our harsher than normal winter some landscapes may take even longer to recover but we need to be patient. The end of March or early April will probably be the best time to determine how much of the lawn will recover. Once new growth occurs we will be better able to decide how much of the lawn needs to be replaced. March is the first month we generally fertilize our lawns but we might consider waiting until the middle or end of March before we apply the appropriate 15-0-15 fertilizers. The ratio of nitrogen to potassium should be 1:1 or 2:1. Avoid using weed and feed products as the nitrogen levels are too high compared to potassium. In addition, it is better to spot treat weeds rather than broadcast the herbicide throughout the whole lawn. Remember 25-30% of the nitrogen in our lawn fertilize should be slow release. Read the fertilizer label carefully to determine if the product you purchase contains the correct amount of slow release fertilizer. As consumers, we should be requesting these types of fertilizers at the garden centers we frequent. For more information on lawn care please attend the free “Landscape Matters” session given at the UF/IFAS Nassau County Demonstration Garden on March 18 at 10am. If you need a diagnosis of your lawn grass problems you can always bring in a sample to the Nassau County Extension satellite office in Yulee on Plant Clinic days anytime between 10am – 2pm. The Plant Clinic dates are: March 16, April 13 & 27, May 11, June 8 & 22, September 14 & 28, and October 12 & 26. The sample should be about the size of a piece of notebook paper. Be sure to include the soil, roots, stolen (runners) and blades (grass leaves). If those dates and times are unsuitable please contact the Extension office to set up an appointment with me, Rebecca Jordi, by calling 904 - 530-6350 or 904 530-6353 or e-mail email@example.com.
Q: Someone told me about a new St. Augustinegrass called Jaymur? Have you ever heard of it?
A: Actually, JaMur is a specific variety of Zoysiagrass which is usually considered a high maintenance lawn. It should be fertilized only twice a year, usually in the spring and fall. It has a tendency to become produce thatch so it may need to be vertically cut or dethatched annually. It does show some ability to tolerate shade and cold which makes it very attractive. Remember, any plant, including grass, will need less water and fertilizer in the shade. The grass blades are much finer than St. Augustine. However, it is susceptible to some of the same disease issues as St. Augustinegrass if it is over watered or over fertilized. In addition, it is susceptible to nematodes.
Q: My husband just came in from cutting the grass and he noticed some small tan-colored moths and some larger brown ones, also a few grasshoppers. How should we best rid our lawn of these pests? I assume they will harm the St. Augustine grass. Please advise us on the best course of action.
A: Several kinds of caterpillars, the immature or larval stage of moths, including sod webworms, armyworms, cutworms and grass loopers may cause damage to all turfgrasses. Bermuda grass is their favorite grass while bahiagrass is the least desirable. Tropical sod webworms, which feed mostly at night, will chew uneven notches along the sides of grass blades. The grass blade may be almost completely stripped off in patches, and these close-cropped areas soon become yellowish to brownish. The damage may start in August but doesn’t become visible until a large portion of the grass is eaten. Adults of the fall armyworm are light brown moths with a wingspan of about 1 1/2 inches. The larvae are present from the spring through the fall. The feeding is similar but more scattered throughout the lawn. However, armyworms feed during the day and rest at night. Damage thresholds vary in different areas but as a rough estimate you need to apply a pesticide if you have 15 or more larvae per square yard. Your local nursery or garden center will have plenty of pesticide options you can use to deal with these pests. Be sure to follow the directions on the label because “the label is the law”. The grasshoppers are difficult to eradicate once they are adults although I would not ignore them. I take great pleasure in crushing them between two bricks if I catch any of them on my citrus.
Q: I have found these rice-like eggs on my grass. They are a light beige color. What are they?
A:What you probably have are the eggs of the armyworm, which is the larva of a moth. Armyworms are common pests found on grass and vegetables. One of the species of army worm prefers Bermuda grass and crabgrass, but they seldom are a severe problem in St. Augustine grass. The face of the mature larva is marked with a white inverted "Y". They are 1-1/2 inches long; they are greenish and have blackish stripes along each side and down the center of the back. In coastal areas of north Florida, moths are abundant from April to December, but some are found even during the winter months. The adult moths are brownish gray. Their wings measure about 1-1/2 inches across when expanded, so you can see they are quite small. The armyworm and the fall armyworm are common species. When they are numerous, they may devour the grass down to the ground. Their feeding causes circular bare areas in lawns. Armyworms spend the winter as pupae or as mature larvae which pupate in the spring. Moths emerge in the spring, mate, and lay eggs in masses on host plants (mostly in the grass family). Larvae feed for about 4 weeks but do most of their damage during the last 10 days of this period. When I see these on my lawn or vegetables I pick them off and throw them away. It seems wasteful to spread insecticide all over the lawn for one or two leaves. I had a few problems last year with army worms, but by hand picking them I have seen none this year. I have even hand picked them off my neighbors yard - I freely admit it has become an obsession. Checking over your lawn and landscape plants (called scouting) can save you a world of trouble by catching problems early.
Q: I am finding brown streaks across my St. Augustine grass and I am seeing the same problem in some of my neighbor’s yards too. What could be causing this problem?
A: Since we talked on the phone and you had several neighbors willing to meet, I went to your subdivision and conducted an extension program called “Troubleshooting Landscapes.” Once I saw your lawns it appeared to be chinch bug damage. Upon further examination we discovered chinch bugs and I was able to show each of you what the insects looked like and how to control them. We discussed proper cultural methods of watering, mowing and fertilization in addition to appropriate chemical applications. Most people are surprised at the small size of chinch bugs especially when compared to the damage they inflict. At this point, all types of St. Augustine are susceptible to chinch bug damage so scouting for these insects during the summer months is important. Try to alternate the chemical you use and restrict the number of applications of the insecticide according to the label. Any homeowner can check their own lawns by taking an empty coffee can and removing the top and the bottom to form a hollow cylinder. Sink the empty coffee can into the grass about 2 inches deep in a section between the dead and dying grass. Slowly poor water into the cylinder keeping the water just above grass level and if chinch bugs are present they should float to the top. The adult chinch bugs are black and white; the nymphs are red and white. Currently, chemicals must be applied to control chinch bugs. There are no cultural practices that will prevent chinch bug damage. Chinch bugs like environments that are hot and dry, so they often start in grass areas where irrigation systems are not overlapping. Check your lawn sprinklers to see that all areas of your lawn are being watered thoroughly, but not over-watered. Remember to water your grass once every 5-7 days in the summer, ¾ inch at a time.
Q: What is wrong with my grass? More then half my neighborhood has dying grass. Any ideas?
In the past two weeks I have had a least a dozen office visits with the same problem – lawn grass dying. A few samples had chinch bugs but all of them had some form of fungal root rot or gray leaf spot. The chinch bugs need immediate attention and an insecticide must be applied or the problem will become worse. We do not advocate using insecticide unless we know a problem exists. The fungal problem has several cultural factors we can change to prevent the problem from becoming so pervasive, although the contributing factor we cannot control is the climate (warm, humid nights). So, let’s work on what we can control. Gray leaf spot grows best when the weather is warm but too much water and high nitrogen fertilizers will enable the fungi to proliferate and the grass will succumb. In many of the cases brought to my office, the roots were in poor condition from watering too frequently and shallowly. The roots should be long (6-8 inches), beige and firm. The best treatment for this disease is prevention. Ideally, the grass should be watered on an “as needed basis”, which means you should set your irrigation systems on manual. Water the grass when you see most of the grass blades (green leaf) fold slightly. Water the grass in the morning hours only, preferably between 6am-10am. Water the grass deeply – about ¾ to 1 inch at a time, once every 5-7 days in the summer, and once every 10-14 days in the winter. Fertilize using a slow release fertilizer such as 15-0-15 or a similar product in March, May and September. The first number promotes growth and the last number helps with roots and stress prevention. Do not apply fertilizer in the summer months as high nitrogen in the warm, humid temperatures contributes to fungal growth. If you want the grass to green up in the summer, use iron sulfate or Ironite with low nitrogen. I know it is not very glamorous to talk about prevention and care because our first reaction is to grab a chemical. However, in the interest of the lawn grass lasting years, it is best if we concentrate our efforts on proper fertilization, watering and mowing. Apply chemicals only when necessary as weeds, insects and disease quickly build resistance to overused pesticides.
Q: My lawn has been looking terrible and my lawn company told me I have sod webworms. I have never seen any worms, what do they look like?
A: Tropical sod webworm larvae are gray-green, have brown spots> on each body segment, and are the smallest of the three lawn grass worms. Mature larvae can be 3/4 to 1 inch in length, and they pupate in the thatch or on the soil surface. Tropical sod webworm adults are small, tan to gray moths with a wingspan of ¾ to 1 inch. They do not cause damage. Moths hide in shrubs and other sheltered areas during the day and fly low when disturbed. Females lay clusters of 6-15 white eggs on grass blades at night. Eggs darken to brown and hatch within 7 days. Tropical sod webworm is most active from April through November in north Florida. Three to four generations occur in Florida each year. Tropical sod webworm larvae feed on St. Augustinegrass, bermudagrass and zoysiagrass. Mow lawn grass at highest height, irrigate properly and apply slow release fertilizers at appropriate times of year. Several major chemical companies make formations specifically for lawn grass and can be purchased at most garden and nursery centers. Be sure to follow the directions on the pesticide label for best results.
Q: Why do some herbicide labels instruct you to spray only when temperatures are between 65 and 85 degrees? Does it really matter?
A: What a terrific question, I know other people have wondered but maybe never got up the nerve to ask. Applying chemicals according to the label absolutely matters. Remember “the label is the law”. This label instruction is a good example of why it is important to follow the directions to the letter of the law. Most plants, regardless of where they are located, begin to slow down their normal growing mechanisms when the outside temperatures begin to drop. The energy of the plant during cold seasons will go to protecting the plant and placing it in a dormant stage. Since the ability of the plant to transfer chemicals throughout the vascular system via the roots is greatly diminished it is of little consequence to apply these herbicides during dormancy. As far as the high temperatures, many plants can be severely damaged or even killed if herbicides are applied when the summer temperatures reach the high eighties. So, the take home lesson is to read and follow the pesticide label. http://edis.ifas.ufl.edu/pi051
Q: Can I use 2,4-D to control weeds in my bahiagrass lawn?
A: The best method of weed control is to maintain a healthy, vigorous turf. Following UF/IFAS recommendations for proper fertilization, irrigation, and mowing will help to maintain a healthy lawn that is able to outcompete most weeds. However, if weed problems persist, the following chemical treatments may be used on bahiagrass for weed control when needed. Post-emergence herbicides are applied to weeds presently growing, it does not control seeds. Post-emergence herbicides (e.g., 2,4-D, dicamba, and/or MCPP) should be applied in May as needed for control of annual and perennial broadleaf weeds, such as knotweed, spurge, and lespedeza. Selective control of emerged grass weeds, such as goosegrass, crabgrass, or alexandergrass, can only be achieved by hand pulling. Sedges can be controlled with applications of halosulfuron. Drop off samples of your weeds for positive identification before applying herbicides. This is important to avoid improper application which wastes money and time – it does not help the environment either. Apply herbicides only when adequate soil moisture is present, air temperatures are between 60°F and 85°F, and the turf is not suffering from water or mowing stress. Failure to follow these precautions will result in damaged turf. For information on controlling weeds in the lawn, please refer to ENH884, Weed Management in Home Lawns, (http://edis.ifas.ufl.edu/ep141). Many popular "weed-n-feed" fertilizers for home lawns contain the herbicide atrazine or metsulfuron. Both of these herbicides will damage bahiagrass; therefore, we do not recommend using weed and feed products on bahiagrass. For these reasons it is critical to read the herbicide label. Remember – “the label is the law.”
Q: I hear from time to time that applying lime to the lawn will kill weeds. I’ve been told that lime is more organic and environmentally safe than chemical weed killers. Is there any scientific basis to this?
A: I have heard this same thing and people often call my office asking me how much lime to apply to their lawns to kill weeds. It is a very popular bit of lore and therefore difficult to convince people to the contrary. Here is what we do know: adding lime to the soil raises the pH causing it to be more alkaline which could possibly cause problems for the growth of the turfgrass you wish to save. Soil pH is important in plant nutrition because it directly effects what elements can be absorbed by plant roots. However, some elements in high concentrations can become toxic to the plant if the soil pH is too high or too low. St. Augustinegrass tolerates a higher soil level but ideally still prefers a slightly acid soil with a pH of around 6.5. Many of our turfgrasses prefer acidic soil conditions (between 5.5 and 6.5) and therefore no lime should ever be added without having the soil tested first from a reputable laboratory. The University of Florida will run a full nutrient test for approximately $7 and your local extension office will run a pH test free of charge or for a nominal fee. One other note, when going on-line to check out information regarding home remedies one should be extremely cautious before using the advice from sources other than research based universities. Once the pH of the soil has reached a certain level it is very difficult to lower it. Getting back to your original question of whether or not lime kills weeds – we have no scientific proof that it does but we do know you can upset the chemical balance of soil by adding lime. The best approach is to stick to true science when working with plants and have the soil tested before adding lime.
Q: How much lime should I add to my lawngrass?
A: None. Please, please do not add lime to your Florida yards unless you have had a soil test that indicates you need it. I have had hundreds of soil test results and only one person has ever had to add lime. I know it is a common practice in northern states to add lime to lawns, but our lawngrass prefers an acid soil (low pH). Liming the yard raises the pH, which places undue stress on the lawn’s ability to absorb important nutrients and minerals. If the pH is too high, it is possible to kill the grass completely. It scares me when I go to garden centers and see large pallets of lime that get shorter and shorter each time I visit. Someone is buying this stuff by the bag full and it should not be the person caring for the lawn. Lime is an important part of vegetable gardening but not lawns. Have I beaten that dead horse enough? You can submit a soil sample to our office (either in Callahan or Yulee) in a paper bag and I will run a pH test free of charge. Please submit only one or two samples as each sample takes about 30 minutes to process and I do not have staff to do this for me. A full nutrient analysis can be run by the University of Florida for a $7 charge per sample, which will include a pH test. Each office has soil test kits you can pick up during normal office hours. Call 904 - 530-6350, (904) 548-1182 for more information.
Q: Some of the University of Florida publications on lawn grasses talk about vertical mowing. What is vertical mowing?
A: The typical lawn mowers used in the home landscape are called rotary as the blades move in a horizontal plane. Vertical mowers have blades which move in a vertical (up/down) plane. This type of mower can be used to remove thatch buildup in lawns. If the thatch layer exceeds 1 inch, it can be removed by vertical mowing, or "verticutting," in early spring to midsummer. It is a messy process and it is difficult for most homeowners to perform properly. Verticutting uses vertical blades which slice through the thatch and slightly into the soil, resulting in large portions of the dead material being removed from the top of the lawn. Usually the blades are spaced about three inches apart which works best for St. Augustinegrass. This type of mowing can cause severe damage to the grass and requires a period of recuperation therefore it is best done when the grass is actively growing. Verticutting should be done in one direction only - not in cross sections. Verticutting will pull out large amounts of grass and thatch which will require cleaning and removal. It will be important to mow the grass directly after verticutting but be sure to mow at the highest height – never scalp or cut the lawn too short. Water the dethatched lawn immediately to avoid dehydration of any exposed roots. One week after vertical mowing, you can apply 15-0-15 fertilizer at the rate of 1 pound of nitrogen per 1000 square feet to encourage recovery. Water the fertilizer in immediately to prevent burning the grass. Periodic topdressing (adding a uniform layer of soil or sand on top of the grass) with ¼ inch of soil matching the current soil is the best method to alleviate thatch accumulation. If topdressing, be sure to use soil free of weed seeds and nematodes and be careful not to exceed recommended topdressing rates. Adding too much soil or organic matter will encourages large (brown) patch disease.
Q: I sometimes hear about different grasses needing either a reel mower or a rotary mower. What are they talking about?
A: Rotary mowers are the typical homeowner mowers that make horizontal cuts to the grass. Rotary mowers operate using electricity or gas. Reel mowers are the old fashioned mowers our grandparents grew up using. Reel mowers make vertical cuts. These mowers can be powered by gas or electricity but our grandparents used their physical strength and pushed the mowers. You can see how that might not be very popular now but it interesting that some of the push mowers are making a come back. The reason we may be seeing a resurgence of the reel mower is probably because of green industry trends. More and more people are becoming interested in doing their part to protect the environment. Reel mowers use no fossil fuel therefore they do not pollute the air. They provide a good source of exercise. What else could get our heart racing better than pushing around a mower at least once a week in the summer? In addition, they are easy to maintain. The blades would need to be cleaned after each use and sharpened at least once during the growing season
Q: I was told to cut my grass very low to prepare for winter. Is that true?
A: I am so glad you called me before you had the lawn mowed. St. Augustine grass should be mowed about 31/2 to 4 inches high so be sure your mower is set on the highest mowing height setting. Cutting it too short can cause it to be stressed and therefore it may succumb to winter chills. The high blade provides food, water and protection to the stolon and roots. Keep it cut high year round. We are entering into the season when lawns will need to be mowed less often so this would be a good time to have mower blades sharpened.
Q: I want to start a new lawn but I can’t afford to sod it all with St. Augustinegrass. What kind of lawn can I start from seed?
A: You have several choices of lawn grass and this is the month to get started. Argentine Bahia, Common Bermuda and centipede grass can all be grown is this area. Do not mix the different grass seeds as each one has specific watering, mowing and fertilizing needs. It would be best to send off a sample of your soil to the University of Florida for testing prior to putting out your seed. All three of the grasses listed above prefer acid soils, so please do not apply lime unless the soil analysis instructs you to add lime. It is important to purchase quality seed. Remove all weeds prior to planting. Sow the seeds in a north-south direction and then repeat in an east-west direction to ensure complete coverage. The seeds should be covered lightly by about ¼ inch of soil to keep them in place. They should be watered in several times a day with a light sprinkling (not soaking) to keep the soil moist – this encourages germination. I am attaching a publication on establishing your Florida lawn to help you with other details. http://edis.ifas.ufl.edu/LH013
Q: I just purchased a property on Amelia Island. The lawn has been neglected for a number of years. It is St. Augustinegrass but in places very thin and of course, weedy. There are a number of large trees to shade which is a problem as well as the leaves. I've been raking leaves and applying a "weed and Feed" product for Southern Lawns. I believe the irrigation system is working OK. Is there anything else I can do to "encourage" this lawn?
A: Welcome to Nassau County. The areas of grass are thin under trees probably because St. Augustinegrass prefers full sun, although 2 varieties (Bitterblue and Seville) will tolerate some shade. Grass grown under trees will typically last a few years but become thinner each consecutive year. Consider planting something else in the area before the weeds completely take over. You might also expand the beds under your trees with mulched areas – just be sure to keep the mulch away from the trunk of any tree or shrub. Some good ornamental alternatives to St. Augustinegrass would be mondo grass, asiatic jasmine, holly fern or dwarf liriope. One other thing, the University of Florida does not recommend the use of “weed and feed” products on St. Augustinegrass - the nitrogen amount is too high compared to the phosphorus and potassium. Consider fertilizing it with a complete fertilizer such as 15-0-15. Look for fertilizers that have a high percentage of slow release nitrogen too- we prefer 1/2. We suggest you fertilize in March, May (if you feel you need to) & September. Use Ironite only in the summer which should contain little or no nitrogen. Water in the morning hours between (6am-10am); apply about 3/4 inch to 1 inch once every 5 days or as needed. If the blade of grass is nice, full and green it does not need to be watered. Shaded areas need less water and fertilizer than plant material in full sun. One other thing, please do not add lime to your yard unless a soil pH test indicates you need it. Although this is a common practice for grasses up north, it is not advisable for lawn grasses here in the south. I will be giving a class on June 22 at the Yulee office at 9am - consider coming in to discuss your specific problems. The class is free and I encourage participants to bring in grass samples (soil, root and all) so we can learn how to check for problems.
Q: I would like to replace my lawn but I want to put out seed rather than sod. What choices do I have other than St. Augustine?
A: We have several grasses that can be established by seed and we would suggest Argentine Bahia, Common Bermuda or Centipede. Centipede is also sold in plugs and sod, so you can plant it a variety of different ways. Argentine Bahia is drought tolerant and requires little maintenance. It is preferred over other Bahia grasses because it produces a smaller V-shaped seed head than the Bahia seed head you often see used along the roadside. Common Bermuda is very hardy for this area and can overtake a St. Augustine lawn if left unchecked. The best time of year to put out seed is late March or April, which is the peak growing season once the fear of frost is over. Check out the University of Florida publication on establishing your lawn and selecting a lawn grass:http://hort.ifas.ufl.edu/yourfloridalawn/ Once you have made your choice on the best lawn grass for your yard, go back to the site and learn how to take care of that specific grass: http://hort.ifas.ufl.edu/yourfloridalawn/ We would also suggest you have your soil tested by the University of Florida for a minimal fee of $7. Test kits, which will need to be mailed to the University of Florida Soil Lab for analysis, can be picked up at the main Extension office in Callahan (near the Fairgrounds) or at the Yulee satellite office at 86026 Pages Dairy Rd . Call us at the Nassau County Extension office (904 530-6353 Callahan or 904 - 530-6350 Yulee) if you have any more questions.
Q: I am tired of replacing the strip of lawn between the sidewalk and the road. If I try to water it properly so much water ends up on the road and the sidewalk and then down the storm drain that I find it discouraging. Now I have to replace it again. Can you give me some other ideas that might be acceptable to my homeowner association?
A: We all know how frustrating it must be to keep those small patches of grass healthy without being wasteful of water and we appreciate your interest in alternatives. Because of the difficulty and wastefulness of these small strips your HOA should be willing to consider some other choices. If you have full sun at this location then you might consider using perennial peanut, Asiatic jasmine, Powderpuff vine or Beach sunflower. Perennial peanut, Arachis glabrata, Benth, spreads by underground rhizomes but does not produce seed which means it will not be carried to wildlife areas by wind or birds. Irrigation will be needed to get the plants established but afterward normal rainfall should be sufficient. It is currently growing at the UF/IFAS Nassau County Extension satellite office in Yulee so take time to come by and see it. Perennial peanut would also be an excellent alternative to grass over sloping berm and it can be planted any time of year. http://edis.ifas.ufl.edu/EP135 Asiatic jasmine, Trachelospermum asiaticum, is a fast growing, evergreen, creeping vine which should completely cover the area within 2 years and should be planted on 18 inch centers. It can easily be edged to keep it in check. It is growing in the Nassau County Demonstration garden at James S. Pages Governmental Complex in Yulee if you wish to see its growth habit. http://hort.ifas.ufl.edu/shrubs/TRASSIA.PDF Powderpuff or Mimosa vine, Mimosa strigillosa, is one of three common native wildflower mimosa vines. Powderpuff is the one most commonly produced for landscapes as it spreads quickly. In a 200 – 300 square feet area only four or five 4 inch pots are needed to cover the area sufficiently. http://edis.ifas.ufl.edu/EP343 Beach sunflower, Helianthus debilis, is a native plant which grows from 2-4 feet tall, can live in any type of soil, and is salt and drought tolerant. The best time of year to plant it is between May and July. For those of you living near the coastal areas, Beach sunflower is an excellent choice. http://edis.ifas.ufl.edu/fp245 These are all attractive and easy to maintain plant choices which should be considered for those common areas in both commercial and residential sites.
Q: I was told my yard needed to be de-thatched. This procedure will be costly, how do I know if I need it done?
A: I get this question quite often and I am glad to have an opportunity to address it. The best information regarding thatch in Florida lawns comes from a University of Florida publication by Dr. Laurie Trenholm, Dr. J.B. Unruh, and Dr. John L. Cisar titled, “Thatch and Its Control in Florida Lawns”. I have pieced together portions of the article which should answer some important questions about thatch. “ Thatch is defined as an intermingled layer of dead and living shoots, stems, and roots that develop between the zone of green vegetation and the soil surface. Thatch consists of a loosely interwoven collection of plant matter that leaves the turf feeling spongy or puffy. Thatch removal should be considered necessary when thatch thickness exceeds one inch. Frequency of that removal will vary, depending on intensity of management. For grasses north of Orlando, the best time for thatch removal is April through July. Vertical mowing at these times ensures quick recovery since warm-season grasses grow rapidly during these periods. After de-thatching, cleanup is necessary. Thatch removed from an average sized lawn may fill several pickup trucks. While the above practice is common on highly managed turf, it is not always needed in home lawns. Homeowners are sometimes convinced that buying this service will improve the condition of their lawns, and may spend unnecessary money on unneeded practices. Thatch is seldom a problem in younger lawns, but can sometimes become a problem in older lawns, particularly ones that have been over-fertilized and over-irrigated.” To look at the entire article please check out the following website:http://edis.ifas.ufl.edu/LH029
Q: Please tell me the proper times to water and how much to water. Are we really supposed to water shrubs differently than grass? I am so frustrated at all the different pieces of information, I just want someone to make it simple for me. BW
A: Thank you so much for your timely question. We will start with the law from the St. Johns River Water Management if we do NOT receive sufficient rain:
- Daylight saving time (DST): Second Sunday in March until the first Sunday in November (summer)
- Eastern Standard Time (EST): First Sunday in November until the second Sunday in March (winter)
- An odd numbered addresses end in 1, 3, 5, 7 or 9. DST – Wednesday/Saturdays; EST Saturdays
- An even numbered addresses end in 0, 2, 4, 6 or 8. DST – Thursday/Sundays; EST Sundays
- Water only when needed and not between 10 a.m. and 4 p.m. *We recommend watering from 4am – 10am so any extra water has time to dry off the blades to reduce disease. We do not suggest watering in the evenings.
- Water for no more than one hour per zone. *We recommend you measure your output with the ideal amount at each watering measuring between ½ inch and ¾ inch. Our grasses grow very well in sandy, well-drained soil and like to be watered deeply but less often to produce strong root structures.
- Restrictions apply to private wells and pumps, ground or surface water and water from public and private utilities. People often believe since they have their own well that is doesn’t matter how much they use but the same restrictions apply to private wells. *We recommend allowing the grass to tell you when to water. Once the blade begins to slightly fold, or has a blue-green color then water the grass.
- *We recommend separating the irrigation zones so the flower beds and hedges are watered differently. Most mature hedges and woody ornamentals do not require irrigation once established and watering twice a week would be excessive and unnecessary. In addition, so many disease issues for lawn grasses and shrubs are caused by over watering.
- *University of Florida/Institute of Food and Agricultural Sciences (UF/IFAS) recommendations.
Q: How much water should your lawn get per week? I give mine one inch every 6 days, including rain. My neighbor waters every other day, rain or shine. I have told him he is just wasting water. What do you think?
A: I know people are going to think I put you up to asking this question, but it is such an important factor in good lawn care that I appreciate you asking it. You are right on target and your lawn in the long run will benefit from your wisdom. The University of Florida suggests 3/4 - 1 inch at each watering. During the summer we suggest once every 5-7 days, in the winter once every 10-14 days. Not only is your neighbor probably wasting water, he is also putting his lawn and landscape shrubs under stress. Under these conditions, many lawn grasses succumb to a variety of fungal diseases and insect stresses. So, keep up the good work you are right on track. Your grass thanks you; the environment thanks you and I thank you!
Q: How much should I be watering my grass during the winter? I just got my water bill and was astonished at how much it is costing me to water the grass. I am watering it ever other day.
A : I have great news for you! No matter what season, water your lawn on an “as needed” basis. That means you should look at the grass blade to determine when it needs water. If the grass blade is flat and green, it is completely hydrated and it needs no water. When you notice the blade beginning to fold onto itself, you should consider applying water. If the grass blade has totally folded onto itself, then the grass is under drought stress and should be watered immediately. Avoid waiting until it reaches drought stress. As a rule of thumb, the University of Florida suggests you water your lawn every 10-14 days in the winter. During the summer months you should water it once or twice a week at the most. Very few plants, including grass, require watering every other day. In fact, over-watering your grass or any plant can create more problems than under-watering. However, you may need to increase the amount of time at each watering in order for the roots to truly receive the necessary amount of water which is equivalent to ½ to ¾ of an inch during each watering session. The only way to know how much water your grass is receiving when you turn on your irrigation system is to measure it. Use empty cat food or tuna cans or even plastic cups to measure the amount of water output from your irrigation system. Check the water level in the containers after 30 minutes, if it has reached the desired limit (1/2 to ¾ of an inch) then your irrigation system is fine. If you need to add or subtract minutes to accomplish the proper amount then simply adjust your automatic timer accordingly. By watering your grass the proper amount, your grass stays healthier and you will be paying a lot less each month on your water bill. Everybody benefits!
Q: I have been using your method of watering only when the blades of grass begin to slightly fold but I am getting concerned about watering in the winter when the grass is brown. I can’t use the blade method then so how do I decide when to water? Do I even need to water?
A: Great question and very timely. I am glad you are setting your irrigation on manual I am sure you are saving money by reducing your water consumption and helping the environment at the same time. The University of Florida suggests you water your lawn grass once every 10 to 14 days during the winter (December through February) if we receive no rain. Remember the blades can be dead but the goal is to keep the stolon (runners) and the roots alive and healthy. Apply no fertilizer during the winter or summer. You can apply a slow release fertilizer (15-0-15) in March, May and September. Be sure to avoid weed and feed products, but use iron sulfate to green it up during the hot weather.
Q: What can you tell me about Zoysiagrass? I am thinking of using it to replace my St. Augustinegrass.
A: We do not have a long history of Zoysiagrass in Northeast Florida. I have only two clients who have planted it recently. Both of them decided to lay sod rather than seed as it takes about two years for the seed to become established. You can imagine the number of weeds which would appear within the early two year period of establishment. The advantages of Zoysiagrass are it can tolerate a wide variety of soil types, tolerate some shade and traffic. The disadvantages are it tolerates drought poorly, requires more nitrogen than most other grasses, and can easily develop thatch. Hunting billbug larvae find Zoysiagrass a delightful meal. It performs poorly in compacted soil but then what plant does not? The publication by the University of Florida discusses several of the more common cultivars. Empire, which is the one you were considering, is more easily obtainable. Keep me posted on your progress, I would love you hear of your success. http://edis.ifas.ufl.edu/pdffiles/LH/LH01100.pdf
Q: I see zoysiagrass advertised locally in the newspapers and was considering choosing it over the St. Augustinegrass. I have even called someone put it down for me. However, when he told me the grass would be coming from Canada I was wondering if that would work well here.
A: I have received several questions about zoysiagrass which means advertising in our local newspapers is working. You are wise to be concerned about a grass grown in Canada surviving here. Certainly the climatic conditions are obviously very different from Northeast Florida not to mention the soil type. However, these facts do not mean zoysiagrass cannot be grown in our area. There are a few vital considerations one of which is where the grass is originally cultivated. The specific cultivar or variety of zoysiagrass selected is equally significant. The advantages of zoysiagrass are its dense growth habit makes weed production difficult, it needs to be mowed less often and some cultivars take foot traffic well, are shade and salt tolerant. Some disadvantages are it has a tendency to develop thatch, it may take two years to become completely established and its shallow root system makes it less drought and insect tolerant in our sandy soil. Some cultivar choices are ‘El Toro’, ‘Palisades’ and ‘Empire’. Check around locally for grasses produced here in Florida – preferably Northern Florida or Southern Georgia which are a closer match to our area. There are zoysiagrass varieties grown in Central and South Florida which would not be the best choice here. The most current University of Florida publication is: http://edis.ifas.ufl.edu/pdffiles/LH/LH01100.pdf
Q: I am considering replacing my St. Augustinegrass with zoysiagrass. What can you tell me about the general care of this grass?
A: I understand you are frustrated with your St. Augustinegrass but there are advantages and disadvantages to all warm season grasses grown in our area. However, if you plan to replace the whole lawn with zoysiagrass it is important to have good information to ensure you make the best selection. Zoysiagrass came to us from Asia and is often used on golf courses or sports fields. However, more varieties have been developed for the home landscape. Zoysiagrass can tolerate a wide range of soils and it has good shade, salt and traffic tolerance. It is slow growing so it does not need to be mowed often. Home lawns should be kept at heights of about 2-3 inches. The blade or leaf of the grass is generally much finer than St. Augustinegrass varieties. Right about now you are thinking it sounds like the perfect grass but there are some disadvantages. One such disadvantage is the slow rate at which it fills in an area. This means if disease or insects destroy a patch, it may take a season or two for Zoysiagrass to completely replenish the damaged spot. Zoysiagrass also has a tendency to develop thatch, which will require removal every few years. Many varieties have high nitrogen and water requirements and therefore high maintenance needs. Some varieties are prone to nematode and disease damage. Nematodes, which are microscopic worms, are common in our sandy soils. For a complete explanation of each of the zoysiagrass cultivars check out the University of Florida publication titled, “Zoysiagrass in Florida”: http://edis.ifas.ufl.edu/pdffiles/LH/LH01100.pdf