Plant Squash (winter) in Zone 10a
Seed-starting, transplant & harvest dates for USDA Zone 10a
Zone 10a averages 323 frost-free days, running from a last spring frost around January 31 to a first fall frost around December 20. Squash (winter) needs roughly 95 days from planting out to first harvest, so it uses about 29 percent of that window. Squash (winter) is a tender crop, which is what decides where in the window it belongs.
Because squash (winter) needs a head start, sow seed indoors around Jan 10, about 3 weeks ahead of the Zone 10a last frost. Transplants go out around Feb 14. Starting earlier than that in Zone 10a usually backfires: plants outgrow their cells and stall when they finally hit cold soil. At 95 days to harvest, a 323-day Zone 10a season has room for about 2 sowings, so stagger them rather than planting everything at once.
Fall planting: squash (winter) in Zone 10a
Squash (winter) has no useful fall window in Zone 10a. Winter squash needs too many days to maturity for a second planting outside the tropics.
Winter squash needs too many days to maturity for a second planting outside the tropics.
Fall dates are counted backward from the Zone 10a average first frost, not forward from a sowing date. See the fall planting calendar by zone for the full method.
Spring vs fall squash (winter) in Zone 10a
| Planting | Sow or start | In the ground | Harvest |
|---|---|---|---|
| Spring | Jan 10 | Feb 14 | May 20 |
| Fall | — | — | — |
Squash (winter) in nearby zones
Further reading on squash (winter)
- When to start seeds indoors by zone
Indoor start dates for squash (winter), counted back from your last frost.
- Hardening off seedlings: a schedule
A day by day plan for moving squash (winter) seedlings outdoors.
- Best grow lights for seed starting
What light seedlings actually need, and which fixtures deliver it.
Other crops in Zone 10a
Frequently asked questions
When should I start squash (winter) in Zone 10a?
Start squash (winter) seeds indoors around Jan 10 (Zone 10a).
Can I direct sow squash (winter) in Zone 10a?
Yes, direct sow around Feb 14.
Can I plant squash (winter) in the fall in Zone 10a?
Squash (winter) has no useful fall window in Zone 10a. Winter squash needs too many days to maturity for a second planting outside the tropics.
Will squash (winter) survive frost in Zone 10a?
No. Squash (winter) is a tender crop and a single light frost ends it, so every Zone 10a planting has to finish before the average first frost.
How many plantings of squash (winter) fit in a Zone 10a season?
About 2. Zone 10a averages 323 frost-free days and squash (winter) needs roughly 95 days plus a couple of weeks of turnaround, so sowing every 55 days keeps a supply coming.