Planting Cleome
Cleome is a warm season flower in the Cleomaceae 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.
Cleome is started indoors 4–6 weeks before your last spring frost date, giving seedlings a head start before they move outside.
Sow Cleome directly into the garden 0–1 weeks after your last frost, once the soil has warmed.
Cleome can be grown by starting indoors and direct sowing. Starting indoors gives the longest, most controlled season, while direct sowing is simplest where the season is long enough.
Spacing and Planting Depth
Give Cleome room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 18 inches |
|---|---|
| Row spacing | 18 inches |
| Plants per sq ft | 0.44 |
| Planting depth | 0.125 inches |
| Sun requirement | Full sun |
Days to Maturity
Cleome reaches maturity in 70–85 days from transplant.
Cleome is ready to harvest after about 78 days. Harvest before the first fall frost, which will end the plant's productive season.
Conditions and Care
As a warm-season flower, Cleome 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.
Cleome needs full sun — give it at least six hours of direct light a day for the best growth and flavor. Sow seed about 0.125 inches deep — small seed is sown shallow and barely covered, then keep the soil evenly moist until seedlings establish.
Cleome belongs to the Cleomaceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Cleome is generally grown as a single planting each season rather than succession sown.
Growing Notes
Tall spider flower; pollinator attractant.