Planting Sunflower
Sunflower is a warm season flower in the Asteraceae family. Getting the timing right is the difference between a strong stand and a disappointing one, so the windows below are given relative to your own last spring frost and first fall frost rather than a generic calendar date. Look up your local frost dates and count back or forward from there.
Sow Sunflower directly into the garden 0–1 weeks after your last frost, once the soil has warmed.
Spacing and Planting Depth
Give Sunflower room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 24 inches |
|---|---|
| Row spacing | 24 inches |
| Plants per sq ft | 0.25 |
| Planting depth | 1 inches |
| Sun requirement | Full sun |
Days to Maturity
Sunflower reaches maturity in 70–100 days from sowing.
For a continuous harvest, sow a new batch every 21 days. Use the succession planting scheduler →
Sunflower is ready to harvest after about 85 days. Harvest before the first fall frost, which will end the plant's productive season.
Conditions and Care
As a warm-season flower, Sunflower needs warm soil and settled weather to thrive, and is set back or killed by frost. It is frost tender, so wait until all danger of frost has passed before planting out and harvest before the first fall frost.
Sunflower needs full sun — give it at least six hours of direct light a day for the best growth and flavor. Sow seed about 1 inch deep, then keep the soil evenly moist until seedlings establish.
Sunflower belongs to the Asteraceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Because it matures relatively quickly, Sunflower rewards succession sowing: small, repeated plantings keep a steady supply coming rather than one short glut.
Companion Plants
Pairing Sunflower with the right neighbors can improve growth and deter pests; a few combinations are best avoided.
Grows well with: Cucumber, Corn
Keep away from: Potato