Milkweed necessary for Monarch Butterflies

By MARY CHUDZYNSKI, MASTER GARDENERMy Nassau Sun

Monarch butterflies have been on earth for more than 10 million years. Today, their very existence is in question, and we find they need to be protected to survive.

Whether it's a field, an urban garden, roadside area, wet area or just an open area, milkweed and flowering plants are needed for monarch habitats. Adult monarchs feed on the nectar of many flowers, but they only breed where milkweed plants are found.

Metamorphosis (stages of development) of the Monarch butterfly takes just 30-40 days and is as follows: 1. Egg, which is about the size of a period in a sentence, is laid by the adult butterfly on the underside of milkweed leaves. 2. Larva is the caterpillar stage where the leaves of the milkweed are consumed. 3. Pupa is the chrysalis phase where nature changes the larva into the butterfly. 4. Adult is the winged mature butterfly.

Monarch Butterfly on Milkweed

Adult monarchs and many other butterfly species love nectar-rich milkweed as a food source, but there is a more important reason for the monarch's close attachment to milkweed. Milkweed is the only plant material monarch caterpillars can eat.

If monarch caterpillars are removed from milkweed they starve or eat other plant material, become sick, and die. Also, milkweed contains a variety of chemical compounds which make monarch caterpillars poisonous to potential predators. These toxins continue to protect monarchs through adulthood.

The scientific name for milkweed is asclepias (pronounced as-KLEE-pea-us). There are several examples of milkweed in Northern Florida:

Common milkweed, asclepias syriaca, is a native to much of the Eastern United States. Common milkweed generally grows to about 48 inches high along roadsides, in fields and in open meadows. It blooms June through July. Common milkweed is utilized as a nectar source by hummingbirds and also by other butterfly species.

Milkweed

Tropical milkweed, asclepias curassavica, also known as bloodflower and Mexican milkweed, is a South American native. Tropical milkweed grows 30-36 inches high and produces clusters of bright yellow or yellow-orange flowers. This plant is highly utilized by monarch butterflies for egg-laying. It's used as a nectar source by many other butterfly species and by hummingbirds.

Swamp milkweed, asclepias incarnata, has clusters of pink or white flowers; the plant grows up to 40 inches high. It blooms May through July. It serves as a nectar source for several butterfly species and as a host plant for monarchs.

In Florida, we do need to be careful which milkweed we plant. Deformed wings on emerging monarchs have become an increasing concern.

These butterflies are infected with a protozoan parasite, ophryocystis elktroscirrha. University of Florida entomologist Jaret Daniels said there is a strong correlation between OE disease and the non-native Mexican milkweed.

 


Master Gardeners

Master Gardener volunteers are trained by County Horticultural Extension agents and are required to serve 75 volunteer hours in the first year of their accreditation and 50 volunteer hours annually in all subsequent years, to maintain their certification.

Nassau County Master Gardeners serve under the direction of Rebecca L. Jordi, UF/IFAS Nassau County Horticultural Extension Agent. For information on the Master Gardener program and application requirements, contact Jordi at 548-1116 or rljordi@ufl.edu.

 

Mary Chudzynski

Mary Chudzynski lives in Fernandina Beach and is an active Master Gardener volunteer.