Annual garden sunflowers are descendents of native plants that were first cultivated by American Indians on the Great Plains for their seeds. Some have become naturalized in the East over the years and are a familiar sight in fields and roadsides in late summer. They are tough, sturdy plants that are easy to grow.
While the traditional sunflowers are tall, with deep golden or brown centers ringed by bright yellow ray petals, cultivated versions are now available in many colors and sizes. They are at home in the landscape, the vegetable garden or in containers, as well as indoors where they are in great demand for flower arrangements. Their nutritious seeds are coveted by backyard wildlife and humans alike.
Size: Annual sunflower varieties range from recently developed dwarf plants up to two feet tall, to the traditional giant types that may exceed 15 feet. The better the soil and moisture situation, the larger the plant and flowers.
Foliage: Sunflower leaves are typically large, egg-shaped, and covered with coarse hairs. The edges of the leaves are shallowly toothed. Stems are stout and hairy. Many varieties are single-stemmed, while others branch repeatedly in order to bear many large flowers.
Flowers: Sunflower blooms have single or double rows of petals which may be mahogany, orange, lemon yellow or red. They bloom in late summer. A sunflower “head” actually contains 2 types of flowers. Each outer “petal” is a small flower in itself, and functions to attract insect pollinators. The center of the head is composed of tiny tubular disk flowers, which later develop into the seeds. Certain newer hybrids do not bear pollen or form seeds. Sunflower heads range from one foot across to only 5- to 6-inches wide.