When to Plant Zucchini
Sow zucchini outside 1 to 3 weeks after your last frost, and again 10 to 12 weeks before your first fall frost for a fall crop.
Zucchini at a glance
- Sow outside
- 1 to 3 weeks after your last frost
- Fall sowing
- 10 to 12 weeks before your first fall frost
- Time to harvest
- 45 to 60 days from sowing
- Harvest lasts
- about 10 weeks
- Spacing
- 1 plant per 4 square feet
- Frost
- Tender: frost kills it
Growing zucchini
One or two zucchini plants feed a household, so resist sowing the whole packet. Sow seeds an inch deep in warm, rich soil in full sun, and give each plant room to spread. Powdery mildew on the leaves late in summer is common and not a reason to worry.
Dates by hardiness zone
Typical dates for each zone; your ZIP code gives your own.
| Zone | Sow | Sow for fall | Harvest |
|---|---|---|---|
| Zone 3a | Jun 4 – Jul 6 | – | Jul 19 – Sep 14 |
| Zone 3b | May 24 – Jun 7 | Jul 3–17 | Jul 8 – Sep 25 |
| Zone 4a | May 19 – Jun 2 | Jul 6–20 | Jul 3 – Sep 28 |
| Zone 4b | May 15–29 | Jul 9–23 | Jun 29 – Oct 1 |
| Zone 5a | May 10–24 | Jul 13–27 | Jun 24 – Oct 5 |
| Zone 5b | May 8–22 | Jul 18 – Aug 1 | Jun 22 – Oct 10 |
| Zone 6a | May 6–20 | Jul 24 – Aug 7 | Jun 20 – Aug 29 · Sep 7 – Oct 16 |
| Zone 6b | Apr 30 – May 14 | Jul 30 – Aug 13 | Jun 14 – Aug 23 · Sep 13 – Oct 22 |
| Zone 7a | Apr 23 – May 7 | Aug 2–16 | Jun 7 – Aug 16 · Sep 16 – Oct 25 |
| Zone 7b | Apr 12–26 | Aug 9–23 | May 27 – Aug 5 · Sep 23 – Nov 1 |
| Zone 8a | Apr 5–19 | Aug 15–29 | May 20 – Jul 29 · Sep 29 – Nov 7 |
| Zone 8b | Mar 24 – Apr 7 | Aug 21 – Sep 4 | May 8 – Jul 17 · Oct 5 – Nov 13 |
| Zone 9a | Mar 9–23 | Sep 3–17 | Apr 23 – Jul 2 · Oct 18 – Nov 26 |
| Zone 9b | Feb 15 – Mar 1Nights are still cool before mid-February, so this starts a little later. | Sep 22 – Oct 6 | Apr 1 – Jun 10 · Nov 6 – Dec 15 |
| Zone 10a | Feb 15 – Mar 1 | Oct 4–18 | Apr 1 – Jun 10 · Nov 18 – Dec 27 |
| Zones 10b–11b | Frost is rare here, so zucchini can go in from late winter, and again in late summer for a fall crop. | ||
Good neighbors
Questions about zucchini
Why do zucchini flowers fall off without fruit?
The first flowers are often male and simply drop after blooming. Female flowers, with a tiny zucchini behind them, follow a week or two later. If young fruits shrivel, move pollen by hand with a small brush.
How big should zucchini be when picked?
Small to medium, about the length of a hand. Larger ones turn seedy and watery, and leaving them on slows the plant down.
