Cleome (Spider Flower) in Zone 10a & 10b

Cleome hassleriana

When to plant cleome (spider flower) in zone 10b

Zones 10a and 10b share the same average frost dates in our data, so this page covers both.

Method: Either: Start indoors for an earlier harvest, or direct-sow outside for less fuss. Cleome (Spider Flower) tolerates either.

Start indoors	Dec 12–Dec 19
Direct sow / transplant outside	Feb 13–Feb 20
Estimated bloom	Apr 29–May 6 (~75 days after planting)

Spacing: 1 per square foot (square-foot-gardening spacing). Mature height: 1.5-6 ft.

Cleome, also called spider flower, is one of the taller plants on this site, anywhere from 1.5 to 6 feet depending on the cultivar, and it earns that height by being a serious draw for hummingbirds, bees, butterflies, and predatory insects that help keep pest populations down elsewhere in the garden. The classic species form does have a downside worth knowing up front: sticky sap, a noticeable odor, and stems armed with small spines.

How cleome (spider flower) fits zone 10's season

Zone 10b's frost-free window runs about 324 days, from January 30 to December 20. Cleome (Spider Flower) needs about 75 days from sowing to first harvest.

Good companions

No standout companions recorded yet for Cleome (Spider Flower).

Where to buy cleome seeds

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