ENH842 Native Wildflowers: Propagation and Container Production of 'Flora Sun' Beach Sunflower1 Jeffrey G. Norcini and James H. Aldrich2 1. This document is ENH842, one of a series of the Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date August 31, 2001. Reviewed September 26, 2001. Visit the EDIS Web Site at http://edis.ifas.ufl.edu. 2. Associate Professor and Senior Biological Scientist, respectively. North Florida Research and Education Center, Quincy, FL 32351. The Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research, educational information and other services only to individuals and institutions that function without regard to race, color, sex, age, handicap, or national origin. For information on obtaining other extension publications, contact your county Cooperative Extension Service office. Florida Cooperative Extension Service/Institute of Food and Agricultural Sciences/University of Florida/Christine Taylor Waddill, Dean. Description 'Flora Sun' beach sunflower (Helianthus debilis ssp. debilis Nutt. 'Flora Sun') is a native, herbaceous perennial for full sun that is salt and drought tolerant. It was released by the U.S. Department of Agriculture, Natural Resources Conservation Service's Plant Materials Center in Brooksville, FL (1). This mounding groundcover is 1 to 3 ft tall and up to 5 ft wide, with plant size in the lower end of the range in drier, less fertile sites. It has deep green leaves with showy yellow flowers ~1 to 11/2 inches in diameter. Flowering is year round in South Florida, and from late spring through frost in North Florida. 'Flora Sun' beach sunflower is best adapted to the immediate Gulf Coast from Florida to Texas, and along the Atlantic coast as far north as the extreme southern coast of South Carolina (1). Further inland it should be treated as a tender perennial or an annual that may reseed, especially in nonmulched situations (1). 'Flora Sun' beach sunflower should not be used along much of the peninsular Gulf coast of Florida (especially from Pasco to Collier County) to avoid crossing with the endangered species Helianthus debilis Nutt. subsp. vestitus (E. Watson) Heiser (2). Figure 1. 'Flora Sun' Beach Sunflower Propagation 'Flora Sun' beach sunflower should be propagated by cuttings. Take 4-inch stem cuttings any time of the year, and remove all but the two terminal leaves. Cuttings should readily root without any rooting compounds* in 2 to 3 weeks under intermittent mist in a shaded (30% light exclusion) greenhouse. During warmer times of the year, we use a misting frequency of 9 sec/2.5 min, with cooling fans (fan/pad system) set to run at =90oF. A propagation heating mat may be necessary during
Native Wildflowers: Propagation and Container Production of 'Flora Sun' Beach Sunflower 2 cooler times of the year to maintain rooting medium temperature at 70oF. Seed propagation is not recommended because 'Flora Sun' beach sunflower could hybridize with other sunflowers, resulting in seed-propagated plants with characteristics unlike those of 'Flora Sun'. Container Production Transplant rooted liners into 1-gal pots containing a well-drained, soilless nursery mix such as pine bark:Canadian sphagnum peat:sand (3:1:1; by vol.) amended with controlled release fertilizer (medium rate) and micronutrients. Potted liners should be acclimatized under 30 to 40% shade for 2 weeks before moving to full sun. Plants should be approximately 6 inches tall and 1 ft wide about 5 to 6 weeks after liners are transplanted into 1-gal containers. Pests The only significant insect or disease pests that have been noted under our propagation and growing conditions have been whitefly (greenhouse only) and leaf spot (Pseudomonis syringae). Insecticidal soap can be used to suppress whitefly infestations. Leaf spot, which primarily affects older leaves, tends to occur only when media fertilizer levels are low. Weeds should be controlled manually since no herbicides are specifically labeled for use on 'Flora Sun' beach sunflower. Availability Breeder material of 'Flora Sun' beach sunflower is currently being maintained by the U.S. Department of Agriculture, Natural Resources Conservation Service Plant Materials Center, Brooksville, FL. _______________ While a quick dip (3 sec) of up to 2000 ppm K-IBA improved rooting, we have noted that the ultimate survival of plants after rooting and container growth was 83% for nontreated cuttings and 57% for cuttings treated with K-IBA. References 1. Anonymous. 1994. 'Flora Sun' beach sunflower. U. S. Dept. Agric. Soil Conserv. Serv., Brooksville, FL. 2. Barnett, M.R. and D. Crewz, eds. 1992. Helianthus debilis Nutt.; dune sunflower, beach sunflower. Fla. Agr. Expt. Sta. SGEF-28, Gainesville, FL.