In Connecticut, the last spring frost usually comes between April 18 and May 9, and the first fall frost between October 6 and October 24, depending on where you live. Most of Connecticut is in USDA hardiness zones 6a to 7a.
Find the frost dates for your ZIP code
Frost dates from NOAA 1991–2020 U.S. Climate Normals, nearest weather station. Zones derived from the 2023 USDA Plant Hardiness Zone Map data (PRISM Climate Group, Oregon State University). This is not the official USDA Plant Hardiness Zone Map.
Frost dates for Connecticut cities
Dates come from the NOAA weather station closest to each city. The last spring frost and first fall frost are the typical dates, with a 30% chance of frost after (or before) them. The safer planting date has only a 10% chance of a later spring frost: use it for tender plants like tomatoes, peppers and basil.
| City | Zone | Last frost | Safer date | First frost |
|---|---|---|---|---|
| Bridgeport | 7a | April 9 | April 17 | Nov. 1 |
| New Haven | 7a | April 22 | May 1 | Oct. 20 |
| Stamford | 7a | April 23 | May 2 | Oct. 16 |
| Hartford | 6b | April 23 | May 1 | Oct. 20 |
| Waterbury | 6b | May 1 | May 9 | Oct. 11 |
| Danbury | 6b | May 6 | May 16 | Oct. 7 |
| Enfield | 6b | April 27 | May 6 | Oct. 10 |
| Norwich | 6b | April 21 | April 30 | Oct. 17 |
| Torrington | 6a | May 14 | May 22 | Oct. 1 |
| Mansfield | 6b | April 25 | May 3 | Oct. 15 |
Frost dates vary a lot across Connecticut. Among the cities above, Bridgeport has the earliest last frost (around April 9) and Torrington the latest (around May 14), about 5 weeks apart. Elevation, nearby water and local terrain all make a difference, so use the dates for the place closest to you, or look up your ZIP code.
Growing zones in Connecticut
Most of Connecticut is in USDA hardiness zones 6a to 7a. A typical frost-free growing season lasts about 189 days, longer in the warmest areas and shorter in the coldest.
Find planting dates for the main zones in Connecticut:
- Zone 6 (about 76% of ZIP codes): Tomatoes, Peppers, Potatoes, Lettuce, Green beans, Cucumbers, Garlic, Tulips
- Zone 7 (about 24% of ZIP codes): Tomatoes, Peppers, Potatoes, Lettuce, Green beans, Cucumbers, Garlic, Tulips
See all crops in our planting guides, or build a planting calendar for your ZIP code.
How to use frost dates
- Cool-season crops such as peas, lettuce, spinach and onions can go in several weeks before your last spring frost.
- Warm-season crops such as tomatoes, peppers, squash and beans wait until after it, when the soil has warmed.
- Fall crops are timed back from your first fall frost, and garlic and tulips are planted around it.
- Frost dates are averages. Check the forecast before setting out tender plants.
Frequently asked questions
When is the last frost in Connecticut?
It depends on where you live. Across most of Connecticut, the last spring frost comes between April 18 and May 9. In Bridgeport, it is around April 9.
When is the first frost in Connecticut?
Across most of Connecticut, the first fall frost comes between October 6 and October 24. In Bridgeport, it is around November 1.
What planting zone is Connecticut?
Most of Connecticut is in USDA hardiness zones 6a to 7a. Enter your ZIP code above to find your exact zone.
When can I plant tomatoes in Connecticut?
Plant tomatoes outside after your last frost, once nights stay above 50 °F. In Bridgeport, the safer date, with only a 10% chance of a later frost, is around April 17. See when to plant tomatoes in zone 7.
Sources. Frost dates come from the nearest NOAA weather station to each city or ZIP code. Zones come from the 2023 USDA Plant Hardiness Zone Map ZIP code data. Our zone lookup is not the official USDA map.