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Frost dates for New Haven Tweed AP, CT

NOAA weather station USW00014758 at 3 ft elevation. Based on 19 years within 1991-2020. Last verified 2026-10-17.

Last spring freeze (32°F)

Apr 17

median: freeze still happened after this date in half of years

Apr 22 30% risk · May 1 10% risk

First fall freeze (32°F)

Oct 27

median: a freeze had happened by this date in half of years

Oct 11 10% chance of a freeze earlier than this

Freeze-free season

193 days

median length between last spring and first fall 32°F freeze

How to read these dates

Spring: a "10% risk" date means NOAA's 1991-2020 data put the chance of a 32°F or colder night after that date at 10%. The "30% risk" date is the convention used by some popular frost calculators (the Old Farmer's Almanac says it uses a 30% probability threshold, source). Fall: a "10%" date means a 10% chance the first freeze comes before it. Source: NOAA readme.

Full table for this station

ThresholdSpring: latest-freeze date at risk of 10% / 30% / 50%Fall: first-freeze date at chance of 10% / 50%
36°F (frost possible)May 12 / May 4 / Apr 30Oct 4 / Oct 15
32°F (freeze)May 1 / Apr 22 / Apr 17Oct 11 / Oct 27
28°F (hard freeze)Apr 18 / Apr 9 / Apr 4Oct 22 / Nov 6

Also at 32°F, last-freeze 70% date Apr 11 and 90% date Apr 2 (frost still likely after these early dates). Data quality: Representative: 10+ years of qualifying data, missing months filled from nearby stations. Source: NOAA NCEI U.S. Climate Normals 1991-2020, station USW00014758, read 2026-10-17.

Is Memorial Day safe here?

Many New England gardeners wait for Memorial Day (it falls between May 25 and May 31). At this station, NOAA's chance of a 32°F or colder night after May 25 is under 10%, and after May 31 is under 10%. Your own spot may differ. See all stations.

Your planting schedule

Pick how cautious you want to be. The dates apply UNH Extension's per-crop rules (UNH fact sheet, read 2026-10-17) to this station's last-freeze date. UNH's sheet does not say which probability its "last frost" means, so you choose. These are planning dates, not instructions; follow your seed packet and the weather.

Last-frost reference date

Showing the schedule for the 2027 season (dates repeat yearly). Table below defaults to Typical; it updates when you choose.

CropStart seeds indoorsOutdoorsUNH Extension rule used
SpinachJan 28 – Mar 4Set out Mar 11 – Apr 1Start 4-6 wk before set-out; set out 3-6 wk before last frost.
BroccoliFeb 11 – Mar 11Set out Mar 25 – Apr 8Start 4-6 wk before set-out; set out 2-4 wk before last frost.
Brussels sproutFeb 11 – Mar 11Set out Mar 25 – Apr 8Start 4-6 wk before set-out; set out 2-4 wk before last frost.
CabbageFeb 11 – Feb 25Set out Mar 25Start 4-6 wk before set-out; set out 4 wk before last frost.
KaleFeb 11 – Feb 25Set out Mar 25Start 4-6 wk before set-out; set out 4 wk before last frost.
KohlrabiFeb 11 – Feb 25Set out Mar 25Start 4-6 wk before set-out; set out 4 wk before last frost.
LeekJan 14 – Jan 28Set out Mar 25Start 8-10 wk before set-out; set out 4 wk before last frost.
LettuceFeb 18 – Mar 4Set out Mar 25 – Apr 1Start 4-5 wk before set-out; set out 3-4 wk before last frost.
OnionJan 14 – Jan 28Set out Mar 25Start 8-10 wk before set-out; set out 4 wk before last frost.
Radish—Sow Mar 25 – Apr 8Sow seed in garden 2-4 wk before last frost.
Turnip—Sow Mar 25 – Apr 8Sow seed in garden 2-4 wk before last frost.
ParsleyJan 21 – Feb 4Set out Apr 1 – Apr 8Start 9-10 wk before set-out; set out 2-3 wk before last frost.
CauliflowerFeb 25 – Mar 11Set out Apr 8Start 4-6 wk before set-out; set out 2 wk before last frost.
Potato—Sow Apr 8 – Apr 15Plant seed potatoes 1-2 wk before last frost.
Swiss chardFeb 25 – Mar 11Set out Apr 8; or sow Mar 25Start 4-6 wk before set-out; set out 2 wk before last frost; or sow seed 4 wk before last frost.
Bean—Sow on/after Apr 22Sow seed in garden after last frost.
CeleryJan 28 – Feb 11Set out on/after Apr 22Start 10-12 wk before set-out; set out after last frost.
Parsnip—Sow on/after Apr 22Sow seed in garden after last frost.
CucumberApr 1 – Apr 15Set out Apr 29 – May 6
Direct sow when soil reaches 70°F		Start 3-4 wk before set-out; set out 1-2 wk after last frost; or sow when soil warms to 70°F.
Sweet potato—Plant slips Apr 29 – May 6Plant slips (young plants) 1-2 wk after last frost.
TomatoMar 4 – Mar 25Set out Apr 29 – May 6Start 6-8 wk before set-out; set out 1-2 wk after last frost.
BasilMar 11 – Mar 25Set out May 6Start 6-8 wk before set-out; set out 2 wk after last frost.
EggplantFeb 25 – Mar 18Set out May 6 – May 13Start 8-10 wk before set-out; set out 2-3 wk after last frost.
MelonApr 8 – Apr 15Set out May 6Start 3-4 wk before set-out; set out 2 wk after last frost.
PepperFeb 25 – Mar 11Set out May 6Start 8-10 wk before set-out; set out 2 wk after last frost.
PumpkinApr 8 – Apr 15Set out May 6
Direct sow when soil reaches 70°F		Start 3-4 wk before set-out; set out 2 wk after last frost; or sow when soil warms to 70°F.
Summer squashApr 8 – Apr 15Set out May 6
Direct sow when soil reaches 70°F		Start 3-4 wk before set-out; set out 2 wk after last frost; or sow when soil warms to 70°F.
Winter squashApr 8 – Apr 15Set out May 6
Direct sow when soil reaches 70°F		Start 3-4 wk before set-out; set out 2 wk after last frost; or sow when soil warms to 70°F.
ZucchiniApr 8 – Apr 15Set out May 6
Direct sow when soil reaches 70°F		Start 3-4 wk before set-out; set out 2 wk after last frost; or sow when soil warms to 70°F.
Rutabaga—Sow Jun 15 – Jul 15Sow seed in garden mid-June to mid-July (fixed dates, not tied to frost).
Beet—Sow when soil reaches 45°F (use a soil thermometer)Sow seed in garden when soil warms to 45°F.
Carrot—Sow when soil reaches 60°F (use a soil thermometer)Sow seed in garden when soil warms to 60°F.
Corn—Sow when soil reaches 60°F (use a soil thermometer)Sow seed in garden when soil warms to 60°F.
Pea—Sow as soon as soil thawsSow seed in garden as soon as soil thaws.

Fall: when the garden ends

At this station the median first 32°F freeze is Oct 27; there is a 10% chance of one before Oct 11. Tender crops (tomatoes, peppers, basil) can be damaged at 33-36°F (Almanac.com notes some plants are damaged in that range); the 36°F first-frost date here is median Oct 15 and 10% date Oct 4. UNH Extension notes many fall vegetables tolerate mild frosts down to about 28°F (median first 28°F here: Nov 6), and that row covers can extend the season. UNH: Fall vegetable gardening, read 2026-10-17.

Your garden is not the weather station

This station sits at 3 ft. UNH Extension says first-freeze dates vary "even between relatively close locations, based on factors such as elevation" (source), and notes that gardeners who keep garden journals can use their own records. Gardeners on Reddit describe the same thing: elevation and cold spots change when they can plant (for example r/vermont). Treat these dates as a starting point.

Nearby stations