Sunflowers
Sunflower (Helianthus annuus)
Sunflowers are a perfect choice for the Florida gardener as they are remarkedly easy to grow, and native varities love the summer heat. These cheerful beauties come in a wide range of sizes and come in a variety of warm colors.
Sunflowers grow rapidly, and some species can reach a height of eight feet or more if conditions are right. There are dwarf varieties and a wide range of colors and flower styles to choose from.
When people think of sunflowers, the huge sunflowers that usually come to mind are Helianthus annuus. These are short-lived annuals with large, striking flowers. Most garden cultivars are 4 to 5 feet tall, though some types can grow to 12 feet tall. The familiar flowers have yellowish petals with a brown central disc, and grow to 6 to 12 inches across. Plants are seeded in late winter to early spring in Florida, produce lovely flowers in mid-spring and decline quickly in the heat by late spring to early-summer. Plants in Florida installed in the fall can produce a nice flower display for several weeks in the fall. A recommended cultivar for Florida is 'Valentine'.
Swamp sunflower (Helianthus angustifolius) is a fall-blooming perennial that can carry a touch of summer into the fall garden. Starting in late summer or early fall, the two- to three-inch flowers appear, sporting rich yellow petals and brown or burgundy centers.
The plants grow four to six feet tall and are perfect for the backs of borders. A hard prune in June keeps them more compact and well-branched. Like all sunflowers, this one performs best when grown in full sun. It’s salt and flood tolerant, making it a good choice for coastal areas and rain gardens. This Florida-Friendly plant is relatively low maintenance but can be prone to infestations of powdery mildew and spittle bugs. You can divide swamp sunflower each year to create new plants, making it easy to pass along to friends.
Even shorter is the beach sunflower (Helianthus debilis), another Florida native perennial. This butterfly-attracting groundcover is perfect for hot, dry sites, including coastal areas.
Sunflowers will tolerate many different soil types and do best in sunny locations. Plant your sunflower seeds during the warm months, and keep in mind that you may need to stake the taller varieties.
Swamp sunflowers (Helianthus angustifolius)
UF/IFAS Publications
- Helianthus angustifolius Swamp Sunflower (PDF)
- Helianthus annuus 'Sonja' Sonja Sunflower
- Helianthus debilis Beach Sunflower