71 days. Stalks average 9 ft. tall and may reach a height of 10 ft. or more. Heads average 11 in. across, with some reaching 14 in. or more when plants are well grown. Gray and black seeds. Space 18 in. apart. Small (7 g) packet has about 70 seeds.
Helianthus annuus unless otherwise noted.
How to grow: Annual. Germination: 14 days, 70 degrees F. Full sun. Direct sow in May or June. Space 12-18” apart. Taller varieties may need staking. Early in the growth stage, place a pole at the base of the stalk. As the stem grows, use twine or soft ties to secure it to the stake every 6’ or so.
History: Some archaeologists believe that Native Americans may have cultivated sunflowers as early as 3000 B.C.
Uses: You can leave any remaining seed-heads in the garden for fall and winter visitors. Or you can cut and dry the seed-heads indoors. Throughout the winter months, tie dried heads to fences or to your deck or suspend in trees to feed birds.