When to plant cucumbers in California
California’s average last spring frost is February 20, and the first fall frost typically arrives around December 1 — about 284 frost-free days (USDA zones 5a, 6b, 7b, 8b, 9b, 10a, 10b). Cucumber needs 50–70 days to mature, which fits comfortably within California's growing season.
California covers a wide range of climates, so your exact frost dates may differ from the state average by two weeks or more. For dates tuned to your town, use the calendar generator.
When to plant cucumbers in California: the short answer
For a spring planting, plant out Feb 27 – Mar 16, with seeds started indoors Jan 23 – Feb 6. Wait until the soil is at least 60°F and frost is over.
Succession sow again in California: Mar 27 · Apr 17 · May 8 · May 29 · Jun 19 · Jul 10 · Jul 31 · Aug 21
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow cucumbers in California, step by step
- Start seeds indoors (Jan 23 – Feb 6). Sow seeds 1 inch deep in seed-starting mix under bright light. They take 3-10 days to sprout, fastest in soil around 85°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. They need at least six to eight hours of direct sun a day and loose soil at least 14 inches deep, with a pH between 5.5 and 7.0. Dig in compost before planting.
- Plant out (Feb 27 – Mar 16). Space plants about 12 inches apart in rows 48 inches apart. It is killed by frost, so nothing goes outside until the danger has passed.
- Water and feed. It needs plenty of water; keep the soil evenly moist and never let it dry out.
- Watch for pests and problems. Pests: striped cucumber beetle, squash bug, aphids, spider mite. Diseases and disorders: powdery mildew, downy mildew, bacterial wilt, angular leaf spot.
- Harvest (from about Apr 25 – May 15). Cucumber takes 50-70 days to reach harvest. Resents root disturbance - if starting indoors use peat/paper pots. Trellising doubles the plants per square foot and cuts disease. A second sowing in midsummer beats early beetle pressure.
Figures come from our crop data; dates use California’s average frost dates. More in the full cucumber growing guide.
Cucumber planting dates by USDA zone in California
California spans USDA zones 5a, 6b, 7b, 8b, 9b, 10a, 10b. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the cucumber dates shift with them.
| Zone | Last frost | First frost | Season | Start indoors | Plant cucumber |
|---|---|---|---|---|---|
| Zone 5 | Apr 30 | Oct 5 | 160 days | Apr 2 – Apr 16 | May 7 – May 24 |
| Zone 6 | Apr 15 | Oct 15 | 185 days | Mar 18 – Apr 1 | Apr 22 – May 9 |
| Zone 7 | Apr 5 | Oct 25 | 200 days | Mar 8 – Mar 22 | Apr 12 – Apr 29 |
| Zone 8 | Mar 20 | Nov 5 | 230 days | Feb 20 – Mar 6 | Mar 27 – Apr 13 |
| Zone 9 | Feb 20 | Nov 30 | 280 days | Jan 23 – Feb 6 | Feb 27 – Mar 16 |
| Zone 10 | Jan 30 | Dec 15 | 330 days | Jan 2 – Jan 16 | Feb 6 – Feb 23 |
Questions gardeners in California ask
When is the best time to plant cucumbers in California?
Plant cucumber transplants outdoors in California between February 27 and March 16. That timing is set by California's average last spring frost of February 20; California spans several climates, so cooler and higher parts of the state run later.
When should I start cucumber seeds indoors in California?
Start seeds indoors between January 23 and February 6, about 3 weeks before the last frost, so the seedlings are ready to plant out from February 27.
Can I plant cucumbers in the fall in California?
Yes. For a fall crop, sow between August 29 and September 15, so the crop matures in cool weather before California's first frost around December 1.
When will cucumbers planted in California be ready to harvest?
Planted on time, cucumbers are usually ready from about April 25 to May 15, 50-70 days after planting.
When is the last frost in California?
On average around February 20, with the first fall frost around December 1 - about 284 frost-free days. Your town may differ by two weeks or more.