Annual flower
Sunflower plant profile
Helianthus annuus
An annual flower for full sun.
Last updated .
When to plant
When to plant Sunflower
Direct sow
at your last spring frost to 2 weeks after your last spring frost
Growing conditions
- Sun
- Full sun
- Planting depth
- 1 in
- Soil pH
- 6 to 6.8
- Lifecycle
- Annual
- Spacing
- 6 to 24 in apart
Common problems
Watch for these
Also watch for: bird damage, deer damage, caterpillars, fungal leaf spots.
Evidence trail
Evidence behind this profile
Original extension and institutional publications behind the planting, care, and safety facts on this page.
- Sunflowers
University of Minnesota Extension. Supports direct-sowing timing (normalized). Checked 2026-06-11.
- Toxic and Non-Toxic Plants: Sunflower (Helianthus annuus) entry
ASPCA Animal Poison Control Center. Supports pet-safety verdicts for dogs and cats. Checked 2026-07-18.