Description
Botanical name
Helianthus
Family
Asteraceae (Compositae)
Spacing
Space seeds about 6 inches apart, then when first true leaves appear, thin to about 60 cm (2′) apart.
Depth
Plant in a shallow trench 2.5-5 cm (1-2″) deep.
Requirements
Prefers well-drained dry or moist soil, but will grow in light (sandy), medium (loamy) and heavy (clay) soils. pH 6.0 to 7.5. Can grow in semi-shade, but full sunlight is best. Can tolerate drought.
Germination
Seeds will sprout in 7-10 days.
Pests
Downy mildew
Timing
Sow seeds directly into the soil after all danger of spring frost is past.
Growing
Water regularly during their most important growth period (about 20 days before and after flowering). Deep, regular watering helps encourage root growth, important for supporting big top-heavy blooms.
Harvest
80-120 days
Season
Warm, perennial