Hartford, CT Frost Dates & Growing Season

The two dates every Hartford garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Apr 17
~50% chance of frost after
First fall frost
Oct 26
~50% chance of frost before
Growing season
192 days
frost-free stretch
USDA zone
6b
2023 hardiness map
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 1 Apr 17 May 1
First fall frost Nov 7 Oct 26 Oct 12
Hard freeze (28°F), median last Apr 3 · first Nov 5

Computed from NOAA 1991–2020 climate normals at the Hartford Brainard Field station (4 km from central Hartford). "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Hartford

Computed from Hartford's own frost dates. Click any crop for the full zone-6 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Feb 20 – Mar 6 Apr 24 – May 1
🫑 Peppers Feb 6 – Feb 20 May 1 – May 8
🥬 Lettuce Mar 6 – Mar 20 Mar 20 – Apr 3 Mar 20 – Apr 17
🫛 Peas Mar 6 – Mar 20
🥕 Carrots Mar 27 – Apr 17
🥦 Broccoli Feb 27 – Mar 13 Mar 27 – Apr 10
🥬 Kale Mar 6 – Mar 20 Mar 20 – Apr 3 Mar 20 – Apr 3
🥒 Cucumbers Mar 20 – Mar 27 Apr 24 – May 1 Apr 24 – May 1
🥒 Zucchini Mar 20 – Mar 27 Apr 24 – May 1 Apr 24 – May 1
🫘 Green Beans (Bush) Apr 24 – May 1
🌽 Sweet Corn Apr 24 – May 1
🌿 Basil Mar 6 – Mar 20 Apr 24 – May 1 May 1 – May 8
🧄 Garlic Fall: Sep 14 – Oct 12

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Hartford's dates automatically after a lookup.

Reading the season in Hartford

Roughly 192 frost-free days gives Hartford gardeners room for nearly every common vegetable. Warm-season crops go out after Apr 17; a fall garden sown in late summer matures comfortably before the Oct 26 frost.

Frequently asked questions

When is the last frost in Hartford, CT?

The average last spring frost in Hartford is around Apr 17, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Hartford, CT?

The average first fall frost in Hartford arrives around Oct 26. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Hartford?

About 192 frost-free days on average, from Apr 17 to Oct 26. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Hartford in?

USDA zone 6b on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.