by Amanda Rose Newton
Monarch butterflies will be making their final pass for the season through Central Florida in the next few weeks as they continue southward to their destination in Mexico.
While still on the endangered list, monarchs are slowly rebuilding their population thanks to the rise in interest in the beautiful butterfly countrywide.
Milkweed, once merely thought of as a plant suited to roadside ditches, has become the best-selling plant at many nurseries– including ours.
For Florida residents, this is not the first instance of the state coming together to support a declining species. By reducing light pollution and carefully preserving beachside habitat, sea turtle numbers have recovered drastically, thanks to community-level support.
Endangered species such as the Monarch butterfly (still on the United States Fish and Wildlife Service’s Federally Endangered List as of this posting) need our support to continue to make their amazing trek across the continent. If you are crazy about monarchs, read on for information on what you can do to help our winged visitors.
Plant the Right Milkweed
Most butterfly enthusiasts know that all monarch caterpillars need milkweed– and a lot of it– to make it to adulthood. By planting more milkweed, gardeners are helping to support populations by supplying the necessary ingredients for life.
Season after season, you are likely to see greater traffic from visiting monarchs, as well as a host of unanticipated life! For more on the fascinating world of milkweed ecology, and how to ensure a nursery is not using pesticides, read our blog here!
However, research in the last decade indicates that the type of milkweed planted could have huge implications for monarch success. Given our location in sunny warm Florida, what we plant could directly play into migratory behavior.
Native Plants Matter
If you have the option, plant native species of milkweed!
Though harder to locate, our native species are equally as enticing and exotic to the monarchs and follow our seasons (what little we have of them) in Florida.
This means that come winter, it will die back to the ground, as they are meant to do. Monarchs travel to Mexico to breed and know to leave the area when the food reserves are low.
By planting natives, you are continuing the tradition and going with the flow of nature, as intended.
What About Tropical Milkweed?
Tropical milkweed has been a controversial topic in the nursery world recently. A decade’s worth of research from the University of Georgia and University of Minnesota reports on the likelihood that planting the species can do more harm than good, especially in warm climates like Florida.
Having a food source available year-round is like having a box of donuts left open on the break room counter…you know you are going back for another!
This has led to many Monarchs overwintering, and in times when we do get a cold snap here in the central part of the state, they will not survive.
As a result, Rockledge Gardens has decided to do our part and not carry milkweed during the winter months and will have it ready for you to purchase next spring.
I know many of us currently already have this planted in our yards and don’t worry! It’s okay! Just cut it back in October and it will be back next year, in time for the natural cyclic rotation of monarchs.
Protozoan OE
One of the reasons tropical milkweed is so concerning is the potential role it plays in the spread of this harmful pathogen (Satterfiled et al. 2015).
When monarchs do not migrate, they end up laying their eggs on the same plants repeatedly throughout the season. This can lead to a build-up of spores deposited by infected monarchs which can increase the prevalence of diseased butterflies seen, and that is what we have been observing in recent years, especially in overwintering sites in South Florida.
Migratory populations show fewer infection rates as a whole, supporting this idea (Batalden & Oberhauser, 2015). Instead of helping with the rise, we are contributing to the fall of populations by giving harboring sites for disease.
What Else Can You Do to Support Monarchs?
Consider Replanting Tropical Milkweed with Native Milkweed- As natives are becoming more available statewide and with helpful tools like the plant locator available from the Florida Native Plant Association website (www.fann.org), it is easier than ever to go native.
Replacing your tropical species little by little can end up having a large impact on monarch longevity.
Educate! We all want to do right by the monarchs, and education is the first step towards success. Spread the word to fellow gardeners and promote growers producing natives. Have a good plant source? We want to know, too!
Become a Citizen Scientist: Become a monarch advocate by participating in monarch tagging and OE testing in your community. Monarch watch can supply you or your group with official monarch tags to help assess the numbers of butterflies completing their journey (www.monarchwatch.org). If you are interested in contributing to the data available on OE infection, we have a limited number of test kits available that can be used next spring when the monarchs are back in town. Kits are also available through the monarch parasite website (www.monarchparasites.org).
Make Your Yard a Monarch Station: Bring attention to both the monarchs and your beautiful yard by applying to be a monarch waystation. In order to be approved, you must have a healthy supply of both nectar and host plants as well as a commitment to using natives when possible. Signs and information are available at www.monarchwatch.org
References and Resources
Oberhauser, K., Nail, K., & Altizer, S. (Eds.). (2015). Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly. Ithaca; London: Cornell University Press.
Satterfield, D. A., Maerz, J. C., & Altizer, S. (2015). Loss of migratory behavior increases infection risk for a butterfly host. Proceedings. Biological Sciences, 282(1801), 20141734. https://doi.org/10.1098/rspb.2014.1734
Malcolm SB, Cockrell B, Brower L. 1993. Spring recolonization of eastern North America by the monarch butterfly: successive brood or single sweep migration? In Biology and conservation of the monarch butterfly (eds SB Malcolm, MP Zalucki), pp. 253–267. Los Angeles, CA: Natural History Museum of Los Angeles
https://monarchjointventure.org/
https://flawildflowers.org/monarch-milkweed/
www.monarchwatch.org
www.monarchparastites.com
