Last spring frost
Apr 27
Frost Dates for Medfield, MA
First fall frost
Oct 14
Growing season
169 days
Hardiness zone
6b
In an average year around Medfield, MA, the last spring frost (32°F) is about Apr 27 and the first fall frost is about Oct 14, giving roughly a 169-day growing season. To be safe most years, wait until Apr 15 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 22 | May 9 | Apr 27 |
| Freeze (32°F) | May 11 | Apr 27 | Apr 15 |
| Hard (28°F) | Apr 26 | Apr 13 | Apr 1 |
| Severe (24°F) | Apr 12 | Mar 31 | Mar 17 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 22 | May 18 | May 14 | May 12 | May 9 | May 6 | May 4 | May 1 | Apr 27 |
| 32°F | May 11 | May 6 | May 3 | Apr 30 | Apr 27 | Apr 24 | Apr 22 | Apr 19 | Apr 15 |
| 28°F | Apr 26 | Apr 22 | Apr 19 | Apr 16 | Apr 13 | Apr 9 | Apr 7 | Apr 4 | Apr 1 |
| 24°F | Apr 12 | Apr 7 | Apr 4 | Apr 2 | Mar 31 | Mar 30 | Mar 26 | Mar 22 | Mar 17 |
| 20°F | Apr 2 | Mar 31 | Mar 29 | Mar 25 | Mar 22 | Mar 19 | Mar 16 | Mar 12 | Mar 7 |
| 16°F | Mar 28 | Mar 22 | Mar 19 | Mar 15 | Mar 13 | Mar 10 | Mar 7 | Mar 3 | Feb 25 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Sep 23 | Oct 3 | Oct 16 |
| Freeze (32°F) | Oct 2 | Oct 14 | Oct 29 |
| Hard (28°F) | Oct 11 | Oct 26 | Nov 10 |
| Severe (24°F) | Oct 23 | Nov 7 | Nov 25 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 23 | Sep 27 | Sep 30 | Oct 2 | Oct 3 | Oct 5 | Oct 8 | Oct 12 | Oct 16 |
| 32°F | Oct 2 | Oct 5 | Oct 8 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 29 |
| 28°F | Oct 11 | Oct 16 | Oct 20 | Oct 23 | Oct 26 | Oct 30 | Nov 1 | Nov 5 | Nov 10 |
| 24°F | Oct 23 | Oct 29 | Nov 2 | Nov 4 | Nov 7 | Nov 11 | Nov 14 | Nov 18 | Nov 25 |
| 20°F | Nov 5 | Nov 11 | Nov 15 | Nov 18 | Nov 22 | Nov 26 | Dec 1 | Dec 3 | Dec 8 |
| 16°F | Nov 19 | Nov 25 | Nov 29 | Dec 2 | Dec 4 | Dec 7 | Dec 11 | Dec 16 | Dec 23 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Walpole 2, Ma, about 3.4 miles away@if(!empty($station['elevation_ft'])), at 170 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Medfield, MA?
On average, the last spring frost (32°F) around Medfield, MA is about Apr 27. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 15.
When is the first frost in the fall?
The first fall frost around Medfield, MA typically arrives about Oct 14. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 27 on average, or Apr 15 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 169 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 02052 Planting calendar → Massachusetts frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026