How to grow zucchini / summer squash
Cucurbita pepo · Cucurbitaceae · Vegetable
When to plant zucchini / summer squash: the short answer
Start seeds indoors about 3 weeks before your last spring frost; plant out about 1 week after it; sow outdoors about 1 week after the last frost; for a fall crop, sow about 12 weeks before your first fall frost. Wait until the soil is at least 60°F; zucchini / summer squash sprout fastest near 85°F.
Zone 5: plant out Apr 30 – May 17. Zone 7: plant out Apr 5 – Apr 22. Zone 9: plant out Feb 20 – Mar 9. See every zone.
Zucchini / Summer Squash is a warm-season vegetable in the Cucurbitaceae family, grown either from a direct sowing or from transplants. It wants full sun (six or more hours of direct light) and consistent moisture — it resents drying out. From sowing to first pick is about 45–60 days. It is killed by frost, so nothing goes outside until the danger has passed and the soil has warmed.
Grower’s note: One or two plants feed a household. A second sowing in early-mid summer dodges the first vine borer generation.
Sowing
Sow about 1″ deep, into soil between 60–95°F — germination is quickest near 85°F. It comes up fast (5–10 days). For an early crop, start seed indoors about 3 weeks before your last spring frost and grow it under bright light.
Spacing & layout
Give each plant about 30″ along the row with roughly 42″ between rows. On a square-foot grid that is one plant per 2 square feet. Allow at least 14″ of loose, workable soil for the roots. It grows well in containers at least 16″ deep.
Fitting it to your season
Zucchini / Summer Squash needs roughly 45–60 frost-free days to crop. Where the season is shorter than that, start it indoors and choose the earliest-maturing varieties, or grow it in a container you can move under cover on cold nights. In long, hot-summer regions it can often be planted twice — once in spring and again in mid-to-late summer for a fall harvest.
Quick facts
Growth stages: how long zucchini / summer squash takes to grow
From sowing to first harvest takes roughly 45-60 days (6-9 weeks), with seedlings appearing after 5-10 days in soil around 85°F.
When to plant zucchini / summer squash
When to plant zucchini / summer squash by USDA zone
Dates worked out from each zone’s typical frost dates for 2026. Find your zone on the zone map, or pick your state below for dates from its own frost dates. Zones 11 and above are frost-free, so timing there depends on heat and rain instead.
| Zone | Last / first frost | Start indoors | Sow or plant out | Fall or second sowing |
|---|---|---|---|---|
| Zone 3 | May 15 / Sep 15 | Apr 17 – May 1 | May 15 – Jun 1 | Jun 13 – Jun 30 |
| Zone 4 | May 10 / Sep 25 | Apr 12 – Apr 26 | May 10 – May 27 | Jun 23 – Jul 10 |
| Zone 5 | Apr 30 / Oct 5 | Apr 2 – Apr 16 | Apr 30 – May 17 | Jul 3 – Jul 20 |
| Zone 6 | Apr 15 / Oct 15 | Mar 18 – Apr 1 | Apr 15 – May 2 | Jul 13 – Jul 30 |
| Zone 7 | Apr 5 / Oct 25 | Mar 8 – Mar 22 | Apr 5 – Apr 22 | Jul 23 – Aug 9 |
| Zone 8 | Mar 20 / Nov 5 | Feb 20 – Mar 6 | Mar 20 – Apr 6 | Aug 3 – Aug 20 |
| Zone 9 | Feb 20 / Nov 30 | Jan 23 – Feb 6 | Feb 20 – Mar 9 | Aug 28 – Sep 14 |
| Zone 10 | Jan 30 / Dec 15 | Jan 2 – Jan 16 | Jan 30 – Feb 16 | Sep 12 – Sep 29 |
Or browse zucchini / summer squash planting dates for every state as static pages.
Companions
Bush Bean, Pole Bean, Sweet Corn, Pea, Radish
Potato
Common problems
Pests: squash vine borer, squash bug, striped cucumber beetle, aphids.
Diseases & disorders: powdery mildew, bacterial wilt, blossom-end rot (calcium disorder).
Same family (Cucurbitaceae)
Rotate these so they don’t follow each other in the same bed year to year.
Questions gardeners ask
When should I plant zucchini / summer squash?
Start seeds indoors about 3 weeks before your last spring frost; plant out about 1 week after it; sow outdoors about 1 week after the last frost; for a fall crop, sow about 12 weeks before your first fall frost. Wait until the soil is at least 60°F. The table on this page gives dates for each USDA zone, and the planting calendar gives dates for your own state or ZIP code.
How long does zucchini / summer squash take to grow?
About 45-60 days from sowing to the first harvest. Seeds germinate in 5-10 days, fastest in soil around 85°F.
How much sun does zucchini / summer squash need?
It needs at least six to eight hours of direct sun a day.
What soil pH does zucchini / summer squash need?
A soil pH between 5.5 and 7.5. It tolerates fairly acidic soil better than most vegetables. Test before adding lime or sulfur - see the soil pH and testing guide.
How far apart should I plant zucchini / summer squash?
Space plants about 30 inches apart in rows 42 inches apart, or one plant per 2 square feet in a square-foot bed. Sow seeds about 1 inch deep.
Can I grow zucchini / summer squash in a container?
Yes. Use a container at least 16 inches deep with drainage holes and a good potting mix, and water more often than you would in the ground.
Figures are typical home-garden ranges from Cooperative Extension planting guides, cross-checked against multiple state sources. Your variety and conditions will vary.