Frost Dates for West Haven, CT
In West Haven, CT, the average last spring frost is around Apr 17 and the average first fall frost around Oct 27, for a growing season of about 193 days. For frost-tender plants, wait until May 1, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the New Haven Tweed Airport, CT weather station, 4 miles away, elevation 3 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.
Frost probability by date
Chance of a 32°F frost after the spring date, or before the fall date.
| Chance | Last spring frost | First fall frost |
|---|---|---|
| 10% | May 1 | Oct 11 |
| 20% | Apr 26 | Oct 16 |
| 30% | Apr 22 | Oct 20 |
| 40% | Apr 20 | Oct 24 |
| 50% | Apr 17 | Oct 27 |
| 60% | Apr 15 | Oct 30 |
| 70% | Apr 11 | Nov 1 |
| 80% | Apr 8 | Nov 4 |
| 90% | Apr 2 | Nov 8 |
Light frost vs. hard freeze
Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.
| Temperature | Last in spring | First in fall |
|---|---|---|
| Light frost (36°F) | Apr 30 | Oct 15 |
| Frost / freeze (32°F) | Apr 17 | Oct 27 |
| Hard freeze (28°F) | Apr 4 | Nov 6 |
Planting calendar for West Haven
Transplant Apr 24 – May 8
Transplant May 1 – May 15
Transplant May 1 – May 15
Transplant Apr 24 – May 8
Sow or transplant Apr 24 – May 8
Sow or transplant Apr 24 – May 8
Sow or transplant May 1 – May 15
Sow or transplant Mar 20 – Apr 3
Fall sowing Sep 1 – Sep 29
Fall sowing Sep 1 – Sep 22
Fall sowing Aug 18 – Sep 1
Sow or transplant Mar 20 – Apr 3
Fall sowing Aug 18 – Sep 15
Transplant Apr 3 – Apr 17
Fall sowing Aug 4 – Aug 18
Transplant Mar 27 – Apr 10
Fall sowing Aug 4 – Aug 18
Fall sowing Aug 4 – Aug 18
Fall sowing Sep 15 – Oct 6
Fall sowing Aug 18 – Sep 1
Plant Mar 20 – Apr 3
Based on the average last frost (Apr 17) and first frost (Oct 27). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.