Lakeside Sunflower, Helianthus carnosus, is one of the more spectacular flowers that was transplanted to our garden from the Bok Towers Garden's Endangered Species Collection. One of the real questions to be answered with our Endangered Plant Showcase is whether the plants would survive and bloom the following year. The Lakeside Sunflower answers, "Yes!" Though plant profiles state the flowering time as early-late summer or August-October, in our southwest Florida garden it began flowering in January. We hope it will continue.
This perennial herb is endemic to the wet prairies and flatwoods of northeastern Florida, and is reported only for Clay, Flagler, Putnam, St. Johns and Volusia counties. It has not been seen in Clay County in many decades. The only known population west of the St. Johns River was reported from Putnam County in 2003.1
H. carnosus is distinguished from other species of Florida sunflowers by its nearly leafless flower stems, yellow disk flowers, and glabrous leaves. The stems are from, 2 - 2.5 feet tall, with 1 - 2 flower heads at top of stem. Flower heads are 2.4 - 4 inches across, with up to 20 yellow ray flowers and many yellow disk flowers on a slightly domed disk. Bracts surrounding the head are loosely overlapping, narrowly oval and pointed, slightly toothed or spiny, and all about the same size. Opposite, smooth leaves, 4 - 10 inches long, linear to lance-shaped, with entire margins and only the midvein visible are mostly clustered near the base of the stem with some small leaves scattered along the upper stem. 2
Photo by Denny Girard.
References:
- Minno MC, Slaughter C (2003) New Record of the Endangered Lakeside Sunflower, Helianthus Carnosus (Asteraceae), From Putnam County, Florida. Florida Scientist: Vol. 66, No. 4 pp. 291-293.
- Florida Natural Areas Inventory, Online Field Guide. http://www.fnai.org/FieldGuide/pdf/Helianthus_carnosus.PDF.