When to plant sunflower in zone 10b — planting calendar

Not your zone?

Showing USDA Zone 10B

Growing SeasonZone 10b

Last frost ~Jan 15First frost ~Dec 31Today

Start indoorsTransplant / sowHarvestFrost risk

JANFEBMARAPR

Sow Jan 15 · First harvest Mar 16 · Wrap by Apr 13

Last spring frostJan 15

Direct sowJan 15

First harvestMar 16

Last harvestApr 13

First fall frostDec 31

Why these dates work in zone 10b

Zone 10b's last spring frost averages Jan 15 and first fall frost Dec 31 — about 350 frost-free days. Sunflower is frost-sensitive, so the around last frost timing builds in a safety margin against a late cold snap — setting plants out too early risks losing them to frost.

Common questions

How long does sunflower take to grow in zone 10b?

Sunflower matures in about 60–100 days from sowing. In zone 10b that means sowing around Jan 15 and first picking around Mar 16.

Will sunflower survive frost in zone 10b?

No — sunflower is frost-sensitive. In zone 10b, wait until after the last frost (around Jan 15) to plant, and harvest before the first fall frost (around Dec 31).

For soil, spacing, pests and companion planting, see the full sunflower growing guide →