When should I plant Squash in Zone 3b?

Start Squash seeds indoors around Apr 17. Transplant outdoors after May 29. Expect first harvest around Jul 13.

What is the last frost date for Zone 3b?

The average last spring frost date for Zone 3b is May 15. The first fall frost averages Sep 22, giving a 130-day growing season.

Can I grow Squash in Zone 3b?

Yes. Squash needs 55 days to harvest. Zone 3b has a 130-day growing season, which is sufficient. You can plant up to 3 successions.

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🟡 Growing Squash in Zone 3b

Zone 3b has harsh winters and a short growing season. Start Squash early indoors to maximize your harvest window. Last frost: May 15. First frost: Sep 22.

Planting Calendar

Indoor

Outdoor

Harvest

Apr 17Sep 22

Season: May 15 – Sep 22 (130 days) · Succession: plant every 3 weeks (up to 3x)

Zone3b

Last FrostMay 15

First FrostSep 22

Season Length130 days

Days to Harvest55

SunFull Sun

Frost ToleranceNone

Spacing1/sqft (12" apart)

When to Plant Squash in Zone 3b

Start Seeds Indoors: Apr 17

Start Squash seeds indoors around Apr 17 (4 weeks before last frost). Optimal germination temperature: 85°F. Germinates in 4–10 days.

Transplant Outdoors: May 29

Transplant Squash seedlings outdoors after May 29. Wait until soil temperature reaches 65°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.

Harvest: Jul 13

First harvest approximately Jul 13 (~45 days from transplant). Continue harvesting until first frost (Sep 22).

Squash in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Plan Your Squash Garden

Track Squash from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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