This post is one of a series from professor Nisse Goldberg's Botany students at Jacksonville University.
|Figure 1. Helianthus debilis, note heart-shaped leaves|
and yellow ray flowers with red-brown disc flowers.
Photo credit: Shirley Denton.
Two subspecies also occur in the state. One of these, H. debilis ssp. cucumerifolius (cucumberleaf dune sunflower), is common in Florida's central and western counties, while the other, H. debilis ssp. vestitus (west coast dune sunflower), is endemic, and found in six counties (from Pinellas south to Lee) along the west coast of the state.
You can recognize the plant by its heart shaped leaves and spreading growth pattern (Figure 1). Its inflorescence is a head (typical of the Asteraceaes) with two types of flowers: yellow ray flowers and reddish-brown disk flowers (Figure 1). H. debilis produces achenes, a dry fruit, and blooms year-round..
This plant plays an important role in beach conservation, used for dune stabilization, wind erosion protection, and beach beautification efforts. It also serves as a source of nectar for butterflies and bees, and its fruits are eaten by birds and other animals found in the dune habitat.
Interested in growing your own? Beach sunflower does best in full sun. Not surprisingly, they are drought-tolerant and grow well in sandy-soils. Vendors that sell the plant can be found using this link from the Florida Association of Native Nurseries: http://www.floridanativenurseries.org/plants/detail/helianthus-debilis-subsp-debilis.
- Christman, S. “Helianthus debilis”. Floridata. 2003. 9 April 2012. http://www.floridata.com/ref/h/heli_deb.cfm.
- “Flora Sun Beach Sunflower”. USDA soil conservation service. http://www.plantmaterials.nrcs.usda.gov/pubs/flpmcbrheded.pdf.
- Gann, G.D., M.E. Abdo, J.W. Gann, G.D. Gann, Sr., S.W. Woodmansee, K.A. Bradley, E. Grahl and K.N. Hines. “East Coast Dune Sunflower”. Natives For Your Neighborhood. 2005-2012. 7 April 2012. http://www.regionalconservation.org.
- Gilman, E.F and Sydney, P. “Helianthus debilis Beach Sunflower”. EDIS. 2012. University of Florida. 9 April 2012. http://edis.ifas.ufl.edu/fp245.
- “Helianthus debilis”. IFAS. Feser, C., Hazell, J., Sibley, J., Cruz, P., Evans, J.,
- O’Donnell, A., Bradley, K. 7 April 2012. http://lee.ifas.ufl.edu/Hort/GardenPubsAZ/beach_dune_sunflower_Helianthus_debilis.pdf.
- Wunderlin, R. P., and B. F. Hansen. 2008. Atlas of Florida Vascular Plants (http://www.plantatlas.usf.edu/).[S. M. Landry and K. N. Campbell (application development), Florida Center for Community Design and Research.] Institute for Systematic Botany, University of South Florida, Tampa.