Ashburnham, MA frost dates
How Ashburnham compares
- In 8 years out of 10, the last spring frost in Ashburnham falls between April 25 and May 19, a 24-day window. The first fall frost falls between September 24 and October 20.
- The median last frost is 8 days later than the Massachusetts median of Apr 27.
- Its 155-day growing season is longer than 11% of the 510 Massachusetts places with a regular frost season (state median 169 days).
- The last frost is 6 days later than the zone 6a median of Apr 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6a chart.
- The weather station records an average of 163 nights a year at or below 32°F.
- Compared with Nashua, NH, 38 km away, the last frost here is 6 days later than there and the growing season is 7 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 25 |
| 50% (median) | May 5 |
| 10% (safe for tender plants) | May 19 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 24 |
| 50% (median) | October 7 |
| 90% (late) | October 20 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Ashburnham, MA
Ashburnham, MA frost dates — last frost May 5, first frost Oct 7, zone 6a. whenisthelastfrost.com
When to plant vegetables in Ashburnham, MA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 10 – Feb 24 | Apr 7 – Apr 21 | — | — |
| Peppers | Feb 24 – Mar 10 | May 19 – Jun 2 | — | — |
| Eggplant | Feb 24 – Mar 10 | May 19 – Jun 2 | — | — |
| Tomatoes | Mar 10 – Mar 24 | May 12 – May 26 | — | — |
| Lettuce | Mar 10 – Mar 24 | Apr 14 – Apr 28 | Apr 7 – May 12 | Aug 12 – Sep 9 |
| Kale | Mar 10 – Mar 24 | Apr 7 – Apr 21 | Apr 7 – Apr 21 | Jul 29 – Aug 19 |
| Broccoli | Mar 10 – Mar 24 | Apr 21 – May 5 | — | Jul 1 – Jul 22 |
| Cabbage | Mar 10 – Mar 24 | Apr 14 – Apr 28 | — | Jul 1 – Jul 22 |
| Cauliflower | Mar 10 – Mar 24 | Apr 21 – May 5 | — | Jul 1 – Jul 22 |
| Okra | Mar 24 – Apr 7 | May 26 – Jun 9 | May 26 – Jun 9 | — |
| Basil | Mar 24 – Apr 7 | May 12 – May 26 | — | — |
| Peas | — | — | Mar 24 – Apr 14 | Jul 15 – Aug 5 |
| Spinach | — | — | Mar 24 – Apr 14 | Aug 12 – Sep 2 |
| Radishes | — | — | Mar 31 – May 12 | Aug 26 – Sep 16 |
| Cucumbers | Apr 7 – Apr 14 | May 19 – May 26 | May 12 – May 26 | Jul 22 – Aug 5 |
| Zucchini & Summer Squash | Apr 7 – Apr 14 | — | May 12 – May 26 | Jul 29 – Aug 12 |
| Winter Squash & Pumpkins | Apr 7 – Apr 14 | — | May 12 – May 26 | — |
| Melons & Watermelon | Apr 7 – Apr 14 | May 19 – Jun 2 | — | — |
| Carrots | — | — | Apr 14 – May 12 | Jul 15 – Jul 29 |
| Beets | — | — | Apr 14 – May 12 | Jul 29 – Aug 12 |
| Potatoes | — | — | Apr 14 – May 5 | — |
| Swiss Chard | — | — | Apr 21 – May 19 | Jul 29 – Aug 12 |
| Cilantro | — | — | Apr 21 – May 12 | Aug 12 – Sep 2 |
| Green Beans | — | — | May 12 – Jun 2 | Jul 22 – Aug 5 |
| Sweet Corn | — | — | May 12 – May 26 | — |
| Sweet Potatoes | — | May 19 – Jun 9 | — | — |
| Garlic | — | — | — | Sep 23 – Oct 28 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Ashburnham N, MA weather station, about 1 km away (elevation 1,145 ft (349 m)).
Frost dates near Ashburnham
- Ashby May 1 · Oct 9
- Gardner May 2 · Oct 13
- Winchendon May 6 · Oct 1
- Westminster May 2 · Oct 13
- Fitchburg May 1 · Oct 9
- Baldwinville May 6 · Oct 1
- East Templeton May 6 · Oct 1
- West Townsend May 1 · Oct 9
- Templeton May 6 · Oct 1
- Lunenburg Apr 29 · Oct 11
Frequently asked questions
When is the last frost in Ashburnham, MA?
The median last spring frost in Ashburnham, MA is May 5. There is still about a 10% chance of frost after May 19, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Ashburnham, MA?
The median first fall frost is October 7, with about a 10% chance of frost before September 24.
How long is the growing season in Ashburnham, MA?
About 155 days between the median last spring frost and first fall frost.
What planting zone is Ashburnham, MA?
Ashburnham, MA is in USDA hardiness zone 6a.