Plant Zucchini in Zone 5a
Seed-starting, transplant & harvest dates for USDA Zone 5a
Zone 5a averages 156 frost-free days, running from a last spring frost around April 30 to a first fall frost around October 3. Zucchini needs roughly 55 days from planting out to first harvest, so it uses about 35 percent of that window. Zucchini is a tender crop, which is what decides where in the window it belongs.
Because zucchini needs a head start, sow seed indoors around Apr 9, about 3 weeks ahead of the Zone 5a last frost. Transplants go out around May 14. Starting earlier than that in Zone 5a usually backfires: plants outgrow their cells and stall when they finally hit cold soil. At 55 days to harvest, a 156-day Zone 5a season has room for about 2 sowings, so stagger them rather than planting everything at once.
Planting zucchini for a fall harvest in Zone 5a
Yes. Sow zucchini by July 12 in Zone 5a. That is 83 days before the average first frost, which covers the 55 days to maturity plus about two weeks for the slower growth that comes with shortening days, plus a two week margin because frost kills zucchini outright.
One midsummer sowing of zucchini replaces the spring plants right as squash vine borer takes them out.
Fall dates are counted backward from the Zone 5a average first frost, not forward from a sowing date. See the fall planting calendar by zone for the full method.
Spring vs fall zucchini in Zone 5a
| Planting | Sow or start | In the ground | Harvest |
|---|---|---|---|
| Spring | Apr 9 | May 14 | Jul 8 |
| Fall | by Jul 12 | Jul 12 | Sep 5 |
Zucchini in nearby zones
Further reading on zucchini
- When to start seeds indoors by zone
Indoor start dates for zucchini, counted back from your last frost.
- Hardening off seedlings: a schedule
A day by day plan for moving zucchini seedlings outdoors.
- Best grow lights for seed starting
What light seedlings actually need, and which fixtures deliver it.
Other crops in Zone 5a
Frequently asked questions
When should I start zucchini in Zone 5a?
Start zucchini seeds indoors around Apr 9 (Zone 5a).
Can I direct sow zucchini in Zone 5a?
Yes, direct sow around May 14.
Can I plant zucchini in the fall in Zone 5a?
Yes. Sow zucchini by July 12 in Zone 5a. That is 83 days before the average first frost, which covers the 55 days to maturity plus about two weeks for the slower growth that comes with shortening days, plus a two week margin because frost kills zucchini outright.
Will zucchini survive frost in Zone 5a?
No. Zucchini is a tender crop and a single light frost ends it, so every Zone 5a planting has to finish before the average first frost.
How many plantings of zucchini fit in a Zone 5a season?
About 2. Zone 5a averages 156 frost-free days and zucchini needs roughly 55 days plus a couple of weeks of turnaround, so sowing every 35 days keeps a supply coming.