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pH: 6.0–7.5  ·  Well-drained; tolerates poor soil

Low to moderate; avoid excess N

Autumn Beauty is a stunning ornamental sunflower cultivar prized for its multi-colored petals in warm autumn tones—typically blends of burgundy, orange, yellow, and mahogany. Unlike single-color varieties, this cultivar's painterly effect makes it especially popular for cut flowers and dramatic garden displays. Gardeners grow it for both aesthetic appeal and the reliable seed production that feeds birds and pollinators.

Sunflower seeds germinate best at soil temperatures of 50–85°F, with optimal sprouting at 70–75°F. Seeds typically emerge in 7–10 days. They prefer direct soil contact and do not require light to germinate. No pre-treatment is necessary, though soaking seeds for 2–4 hours before planting can slightly speed germination in cool soil.

Direct sow seeds outdoors after the last frost date when soil has warmed to at least 50°F, planting seeds 1 inch deep and 6 inches apart. Thin seedlings to 12–18 inches apart once they develop true leaves, as Autumn Beauty grows to 4–5 feet and needs good air circulation. Sunflowers can be started indoors 3–4 weeks before the last frost, though they prefer direct sowing because transplanting can damage their taproot. For continuous blooms, sow seeds in succession every 2–3 weeks through early summer.

Water deeply once or twice per week, aiming for 1–1.5 inches per week; drought-stressed plants produce smaller flowers. Fertilize lightly at planting with balanced fertilizer; excess nitrogen encourages foliage at the expense of flowers. Tall varieties like Autumn Beauty benefit from staking or support when grown in windy sites or when planted densely. Watch for powdery mildew in humid conditions—improve air circulation and avoid overhead watering. Sunflowers are generally pest-resistant, though birds and squirrels may target developing seeds.

Sunflowers are ready to cut when the back of the flower head turns from green to yellow-brown and petals are fully open, usually 70–100 days from sowing. Cut stems in early morning with a sharp knife, leaving at least 12 inches of stem. For seed harvest, allow flowers to fully mature until the head droops and the back turns brown, then cover with a mesh bag to protect from birds and cut the entire head. Dry seeds indoors for 2–3 weeks, then rub out and store in a cool, dry place for up to a year.