When to plant in New Haven, CT
USDA Zone 7aHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for New Haven, Connecticut — all computed from New Haven's nearest NOAA weather station.
In zone 7a, New Haven supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.
Frost probability
NEW HAVEN TWEED AP · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are New Haven’s own odds, recorded at NEW HAVEN TWEED AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 12 | Apr 30 | Apr 17 | Oct 4 | Oct 15 | Nov 1 |
| 32°F | May 1 | Apr 17 | Apr 2 | Oct 11 | Oct 27 | Nov 8 |
| 28°F | Apr 18 | Apr 4 | Mar 22 | Oct 22 | Nov 6 | Nov 21 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in New Haven, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 15 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
New Haven planting FAQ
When is the last spring frost in New Haven, CT?
On average, the last spring frost in New Haven is around April 17 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in New Haven, CT?
In New Haven, the first 32°F freeze of fall lands around October 27 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is New Haven in?
New Haven is in USDA hardiness zone 7a. In zone 7a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in New Haven?
New Haven has about 193 frost-free days — a moderate growing season — between the average last spring frost (April 17) and first fall frost (October 27).
When should I plant tomatoes in New Haven?
For New Haven, sow tomatoes indoors about February 20–March 6 and move the seedlings out around April 24, after the last spring frost.
Never miss a window in New Haven
An email when it’s time to start seeds, transplant, and sow — timed to New Haven’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- West Haven · 6 km
- East Haven · 6 km
- Orange · 9 km
- North Haven · 10 km
- Ansonia · 13 km
- Derby · 13 km
- Milford · 15 km
- Wallingford Center · 18 km
Frost dates recorded at NEW HAVEN TWEED AP, 6 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in New Haven, CT — Frost Dates & Zone 7a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00014758. Retrieved from https://blissgarden.com/connecticut/new-haven.