Frost dates for Houlton 5N, ME
NOAA weather station USC00173944 at 390 ft elevation. Based on 24 years within 1991-2020. Last verified 2026-10-17.
Last spring freeze (32°F)
May 19
median: freeze still happened after this date in half of years
May 25 30% risk · Jun 2 10% risk
First fall freeze (32°F)
Sep 23
median: a freeze had happened by this date in half of years
Sep 9 10% chance of a freeze earlier than this
Freeze-free season
125 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
| Threshold | Spring: latest-freeze date at risk of 10% / 30% / 50% | Fall: first-freeze date at chance of 10% / 50% |
|---|---|---|
| 36°F (frost possible) | Jun 16 / Jun 7 / Jun 1 | Aug 28 / Sep 10 |
| 32°F (freeze) | Jun 2 / May 25 / May 19 | Sep 9 / Sep 23 |
| 28°F (hard freeze) | May 18 / May 10 / May 4 | Sep 22 / Oct 5 |
Also at 32°F, last-freeze 70% date May 12 and 90% date May 3 (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 USC00173944, 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 10-30%, and after May 31 is 10-30%. Your own spot may differ. See all stations.
UMaine Extension gives central-Maine planting dates and says to plant 10-14 days earlier on the coast and 10-14 days later in northern Maine (read 2026-10-17).
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.
Showing the schedule for the 2027 season (dates repeat yearly). Table below defaults to Typical; it updates when you choose.
| Crop | Start seeds indoors | Outdoors | UNH Extension rule used |
|---|---|---|---|
| Spinach | Mar 2 – Apr 6 | Set out Apr 13 – May 4 | Start 4-6 wk before set-out; set out 3-6 wk before last frost. |
| Broccoli | Mar 16 – Apr 13 | Set out Apr 27 – May 11 | Start 4-6 wk before set-out; set out 2-4 wk before last frost. |
| Brussels sprout | Mar 16 – Apr 13 | Set out Apr 27 – May 11 | Start 4-6 wk before set-out; set out 2-4 wk before last frost. |
| Cabbage | Mar 16 – Mar 30 | Set out Apr 27 | Start 4-6 wk before set-out; set out 4 wk before last frost. |
| Kale | Mar 16 – Mar 30 | Set out Apr 27 | Start 4-6 wk before set-out; set out 4 wk before last frost. |
| Kohlrabi | Mar 16 – Mar 30 | Set out Apr 27 | Start 4-6 wk before set-out; set out 4 wk before last frost. |
| Leek | Feb 16 – Mar 2 | Set out Apr 27 | Start 8-10 wk before set-out; set out 4 wk before last frost. |
| Lettuce | Mar 23 – Apr 6 | Set out Apr 27 – May 4 | Start 4-5 wk before set-out; set out 3-4 wk before last frost. |
| Onion | Feb 16 – Mar 2 | Set out Apr 27 | Start 8-10 wk before set-out; set out 4 wk before last frost. |
| Radish | — | Sow Apr 27 – May 11 | Sow seed in garden 2-4 wk before last frost. |
| Turnip | — | Sow Apr 27 – May 11 | Sow seed in garden 2-4 wk before last frost. |
| Parsley | Feb 23 – Mar 9 | Set out May 4 – May 11 | Start 9-10 wk before set-out; set out 2-3 wk before last frost. |
| Cauliflower | Mar 30 – Apr 13 | Set out May 11 | Start 4-6 wk before set-out; set out 2 wk before last frost. |
| Potato | — | Sow May 11 – May 18 | Plant seed potatoes 1-2 wk before last frost. |
| Swiss chard | Mar 30 – Apr 13 | Set out May 11; or sow Apr 27 | Start 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 May 25 | Sow seed in garden after last frost. |
| Celery | Mar 2 – Mar 16 | Set out on/after May 25 | Start 10-12 wk before set-out; set out after last frost. |
| Parsnip | — | Sow on/after May 25 | Sow seed in garden after last frost. |
| Cucumber | May 4 – May 18 | Set out Jun 1 – Jun 8 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 Jun 1 – Jun 8 | Plant slips (young plants) 1-2 wk after last frost. |
| Tomato | Apr 6 – Apr 27 | Set out Jun 1 – Jun 8 | Start 6-8 wk before set-out; set out 1-2 wk after last frost. |
| Basil | Apr 13 – Apr 27 | Set out Jun 8 | Start 6-8 wk before set-out; set out 2 wk after last frost. |
| Eggplant | Mar 30 – Apr 20 | Set out Jun 8 – Jun 15 | Start 8-10 wk before set-out; set out 2-3 wk after last frost. |
| Melon | May 11 – May 18 | Set out Jun 8 | Start 3-4 wk before set-out; set out 2 wk after last frost. |
| Pepper | Mar 30 – Apr 13 | Set out Jun 8 | Start 8-10 wk before set-out; set out 2 wk after last frost. |
| Pumpkin | May 11 – May 18 | Set out Jun 8 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 squash | May 11 – May 18 | Set out Jun 8 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 squash | May 11 – May 18 | Set out Jun 8 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. |
| Zucchini | May 11 – May 18 | Set out Jun 8 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 15 | Sow 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 thaws | Sow seed in garden as soon as soil thaws. |
Fall: when the garden ends
At this station the median first 32°F freeze is Sep 23; there is a 10% chance of one before Sep 9. 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 Sep 10 and 10% date Aug 28. UNH Extension notes many fall vegetables tolerate mild frosts down to about 28°F (median first 28°F here: Oct 5), 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 390 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
- Houlton Intl AP, ME: 6 mi away, 476 ft elevation, median last 32°F freeze May 27
- Bridgewater, ME: 15 mi away, 420 ft elevation, median last 32°F freeze May 25
- Presque Isle, ME: 32 mi away, 599 ft elevation, median last 32°F freeze May 14
- Patten 2, ME: 34 mi away, 820 ft elevation, median last 32°F freeze May 13
- Danforth, ME: 38 mi away, 475 ft elevation, median last 32°F freeze May 25