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Connecticut Planting Guide & Growing Season

Connecticut is in USDA hardiness zone 5b-7a with a growing season of 170 days. The average last spring frost is Apr 25 and the average first fall frost is Oct 10. Climate data based on Hartford.

USDA Zone 5b-7a Hardiness zone
Last Frost Apr 25 Average spring
First Frost Oct 10 Average fall
Growing Season 170 days Moderate season

Growing Conditions in Connecticut

USDA Hardiness Zone5b-7a
Average Last FrostApr 25
Average First FrostOct 10
Growing Season Length170 days
Climate StationHartford
NOAA GridBOX

How Connecticut Compares

Compare Connecticut's growing conditions with states that have similar climates.

StateUSDA ZoneLast FrostFirst FrostSeason (days)
Connecticut (CT) 5b-7aApr 25Oct 10170
Alabama (AL) 7a-8bMar 15Nov 5235
Alaska (AK) 1a-7bMay 30Sep 5100
Arizona (AZ) 4b-10bMar 1Nov 15260
Arkansas (AR) 6b-8aApr 1Oct 25210
California (CA) 4b-11aFeb 15Nov 30290

Frequently Asked Questions About Gardening in Connecticut

When should I start seeds indoors in Connecticut?

In Connecticut, the average last frost date is Apr 25. Start most seeds indoors 6-8 weeks before this date. The USDA hardiness zone for Connecticut is 5b-7a, with a growing season of approximately 170 days.

What USDA hardiness zone is Connecticut?

Connecticut falls in USDA hardiness zones 5b-7a. This affects which perennial plants will survive winter and influences optimal planting times.

When is the first frost in Connecticut?

The average first frost date in Connecticut is Oct 10. Plan to harvest cold-sensitive crops before this date or protect them with row covers.

How long is the growing season in Connecticut?

Connecticut has an average growing season of 170 days, from the last frost (Apr 25) to first frost (Oct 10). This moderate season works well for most common vegetables.

Plan Your Garden

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