When Is the Last Frost in Massachusetts?
The average last spring frost in Massachusetts falls between April 13 and May 7 for most ZIP codes, with a statewide median of April 27. At the average date a later frost is still a coin flip, so tender plants wait for the safer 90% date.
| City | Last frost | 90% safe after | First frost | Growing season |
|---|---|---|---|---|
| Boston | Apr 4 | Apr 17 | Nov 9 | 218 days |
| Worcester | Apr 23 | May 5 | Oct 21 | 181 days |
| Springfield | May 3 | May 17 | Oct 8 | 158 days |
| Cambridge | Apr 19 | May 3 | Oct 23 | 185 days |
| Lowell | Apr 30 | May 10 | Oct 10 | 164 days |
| Brockton | Apr 22 | May 5 | Oct 19 | 178 days |
| Lynn | Apr 25 | May 13 | Oct 20 | 176 days |
| Quincy | Apr 25 | May 8 | Oct 22 | 177 days |
| New Bedford | Apr 29 | May 15 | Oct 15 | 167 days |
| Fall River | Apr 29 | May 15 | Oct 15 | 167 days |
| Framingham | Apr 26 | May 9 | Oct 12 | 169 days |
| Barnstable Town | Apr 16 | Apr 30 | Oct 30 | 195 days |
| Attleboro | Apr 27 | May 10 | Oct 15 | 168 days |
| Leominster | Apr 29 | May 13 | Oct 11 | 164 days |
| Pittsfield | May 5 | May 21 | Oct 5 | 152 days |
| Amherst Town | May 5 | May 19 | Oct 8 | 156 days |
| Gloucester | May 4 | May 17 | Oct 12 | 160 days |
| Newburyport | May 3 | May 17 | Oct 8 | 158 days |
Last and first frost: 50% (median) dates of the last spring and first fall 32 °F night. 90% safe after: only a 10% chance of a later spring frost. First frost dates in January fall in the following winter. Each city uses the NOAA station nearest the ZIP code closest to its center.
Across all 69 Massachusetts weather stations with frost records, median last frost dates run from April 4 at Boston Logan INTL AP, MA to May 17 at E Hawley, MA. Elevation, valleys that collect cold air and distance from large water bodies explain most of the spread, so a garden a few miles from a listed city can differ by a week or more. The ZIP code lookup above uses the same NOAA data as the frost date calculator for every US ZIP code.
When Is the First Frost in Massachusetts?
The average first fall frost in Massachusetts arrives between October 5 and November 3 for most ZIP codes, with a median of October 15. Tomatoes, peppers, basil and squash are damaged at 32 °F, so harvest or cover them before then.
Fall frost can come early: Boston has a 10% chance of frost before October 29, Worcester has a 10% chance of frost before October 6 and Springfield has a 10% chance of frost before September 26. Hardy crops such as kale, spinach and cabbage tolerate light frosts and keep producing after the first frost date.
When to Plant Tomatoes in Massachusetts?
Transplant tomatoes in Massachusetts 1 to 2 weeks after the local average last frost, once nights stay above about 50 °F: Apr 11 – Apr 18 in Boston, Apr 30 – May 7 in Worcester and May 10 – May 17 in Springfield. Start seeds indoors 6 to 8 weeks before the last frost.
| City | Start seeds indoors | Transplant outdoors | Lowest-risk transplant |
|---|---|---|---|
| Boston | Feb 7 – Feb 21 | Apr 11 – Apr 18 | after Apr 17 |
| Worcester | Feb 26 – Mar 12 | Apr 30 – May 7 | after May 5 |
| Springfield | Mar 8 – Mar 22 | May 10 – May 17 | after May 17 |
| Cambridge | Feb 22 – Mar 8 | Apr 26 – May 3 | after May 3 |
| Lowell | Mar 5 – Mar 19 | May 7 – May 14 | after May 10 |
| Brockton | Feb 25 – Mar 11 | Apr 29 – May 6 | after May 5 |
| Lynn | Feb 28 – Mar 14 | May 2 – May 9 | after May 13 |
| Quincy | Feb 28 – Mar 14 | May 2 – May 9 | after May 8 |
| New Bedford | Mar 4 – Mar 18 | May 6 – May 13 | after May 15 |
| Fall River | Mar 4 – Mar 18 | May 6 – May 13 | after May 15 |
| Framingham | Mar 1 – Mar 15 | May 3 – May 10 | after May 9 |
| Barnstable Town | Feb 19 – Mar 5 | Apr 23 – Apr 30 | after Apr 30 |
| Attleboro | Mar 2 – Mar 16 | May 4 – May 11 | after May 10 |
| Leominster | Mar 4 – Mar 18 | May 6 – May 13 | after May 13 |
| Pittsfield | Mar 10 – Mar 24 | May 12 – May 19 | after May 21 |
| Amherst Town | Mar 10 – Mar 24 | May 12 – May 19 | after May 19 |
| Gloucester | Mar 9 – Mar 23 | May 11 – May 18 | after May 17 |
| Newburyport | Mar 8 – Mar 22 | May 10 – May 17 | after May 17 |
Indoors: 6–8 weeks before the average last frost. Outdoors: 1–2 weeks after it. Lowest-risk: after the date with only a 10% chance of a later frost. Rules of thumb; check the 10-day forecast and wait for soil near 60 °F.
Tomatoes stall below about 50 °F at night and are killed by frost, so a week or two of waiting after the average date costs little. The tomato plant care guide covers light, watering and feeding once plants are in the ground.
What Can You Plant in Boston and When?
Boston's average last frost of April 4 anchors its spring planting calendar: peas and spinach go in from February 21, broccoli and lettuce transplants from March 7, and tomatoes, peppers and squash after April 11.
| Crop | Start seeds indoors | Plant outdoors | Frost tolerance |
|---|---|---|---|
| Peas | — | Feb 21 – Mar 7direct sow, 4–6 weeks before last frost | hardy |
| Spinach | — | Feb 21 – Mar 14direct sow, 3–6 weeks before last frost | hardy |
| Radishes | — | Feb 28 – Mar 14direct sow, 3–5 weeks before last frost | hardy |
| Onions (sets) | — | Mar 7 – Mar 21plant, 2–4 weeks before last frost | hardy |
| Potatoes | — | Mar 7 – Mar 21plant, 2–4 weeks before last frost | half-hardy |
| Broccoli & cabbage | Feb 7 – Feb 21 | Mar 7 – Mar 21transplant, 2–4 weeks before last frost | hardy |
| Lettuce | Feb 21 – Mar 7 | Mar 7 – Mar 21transplant, 2–4 weeks before last frost | hardy |
| Beets | — | Mar 7 – Mar 21direct sow, 2–4 weeks before last frost | half-hardy |
| Carrots | — | Mar 14 – Mar 21direct sow, 2–3 weeks before last frost | half-hardy |
| Tomatoes | Feb 7 – Feb 21 | Apr 11 – Apr 18transplant, 1–2 weeks after last frost | tender |
| Basil | Feb 7 – Feb 21 | Apr 11 – Apr 25transplant, 1–3 weeks after last frost | tender |
| Peppers | Jan 24 – Feb 7 | Apr 18 – Apr 25transplant, 2–3 weeks after last frost | tender |
| Eggplant | Jan 24 – Feb 7 | Apr 18 – Apr 25transplant, 2–3 weeks after last frost | tender |
| Green beans | — | Apr 11 – Apr 25direct sow, 1–3 weeks after last frost | tender |
| Sweet corn | — | Apr 11 – Apr 25direct sow, 1–3 weeks after last frost | tender |
| Cucumbers | Mar 7 – Mar 14 | Apr 11 – Apr 25transplant, 1–3 weeks after last frost | tender |
| Squash & zucchini | Mar 7 – Mar 14 | Apr 11 – Apr 25transplant, 1–3 weeks after last frost | tender |
| Watermelon | Mar 7 – Mar 14 | Apr 18 – Apr 25transplant, 2–3 weeks after last frost | tender |
Dates for Boston (last frost Apr 4, NOAA station Boston Logan INTL AP, MA, 2 miles from ZIP 02127). General rules of thumb; wait for soil near 50 °F for most seeds and 60 °F for beans, corn and squash.
How Long Is the Growing Season in Massachusetts?
The frost-free growing season in Massachusetts lasts about 152 to 204 days for most ZIP codes, with a median of 169 days. Among the listed cities, Pittsfield has the shortest season at 152 days and Boston the longest at 218.
Season length decides which varieties ripen: compare it with the “days to maturity” on seed packets, counted from transplanting for tomatoes and peppers. NOAA stations in Massachusetts range from 136 days at E Hawley, MA to 221 days at Chatham, MA. Planning beds before the season starts helps in short seasons — a plant spacing calculator for vegetable beds shows how many transplants fit.
What Hardiness Zones Are in Massachusetts?
Massachusetts spans USDA hardiness zones 5b to 7b, with zone 6b the most common. Zones describe winter cold and decide which perennials survive, while frost dates set when to plant annual vegetables and flowers.
The Massachusetts planting zone map with the zone of each city shows how the zones are spread across the state and which plants are hardy in all of them.
Frequently Asked Questions
- When is the last frost in Massachusetts?
- The average last spring frost in Massachusetts falls between April 13 and May 7 for most ZIP codes, with a statewide median of April 27. Among major cities it ranges from April 4 in Boston to May 5 in Amherst Town.
- When is the last frost in Boston, Massachusetts?
- Boston's average last spring frost is April 4, and by April 17 the chance of a later frost drops to 10%. Its first fall frost averages November 9, giving a 218-day growing season (NOAA station Boston Logan INTL AP, MA).
- When should you plant tomatoes in Massachusetts?
- Transplant tomatoes in Massachusetts 1 to 2 weeks after the local average last frost, once nights stay above about 50 °F: Apr 11 – Apr 18 in Boston, Apr 30 – May 7 in Worcester and May 10 – May 17 in Springfield. Start seeds indoors 6 to 8 weeks before the last frost.
- When is the first frost in Massachusetts?
- The average first fall frost in Massachusetts arrives between October 5 and November 3 for most ZIP codes, with a median of October 15. Harvest tender crops such as tomatoes, peppers and basil before then or cover them on cold nights.
- How long is the growing season in Massachusetts?
- The frost-free growing season in Massachusetts lasts about 152 to 204 days for most ZIP codes, with a median of 169 days, from 152 days in Pittsfield to 218 days in Boston.
Frost data: NOAA National Centers for Environmental Information, 1991–2020 U.S. Climate Normals (32 °F freeze dates by probability). ZIP code and city locations and populations: U.S. Census Bureau Gazetteer files and Vintage 2024 population estimates. Planting windows are general rules of thumb. PlantoScan is not affiliated with or endorsed by these agencies.