Sunflower, Helianthus annuus, is an herbaceous annual plant in the family Asteraceae, grown for its seeds. The plant has a thick, hairy, erect stem which gives rise to a large flower head.
They are hardy and do not require fertilizer, but a little phosphorus and potassium can encourage bigger blooms, a little nitrogen supports leaf growth.
They thrive in sandy or well-drained soil, slightly acidic to somewhat alkaline (pH 6.0 to 7.5) and love organic compost.
The blossom of the sunflower is called a head. The yellow petals and fuzzy brown centers are actually individual flowers themselves. As many as 2,000 can make up the sunflower bloom.
