Gardner, MA planting zone & frost dates
Gardner is in USDA hardiness zone 5b. The last spring frost usually comes around May 2 and the first fall frost around October 13, for a growing season of about 163 days.
Planting calendar for Gardner
Dates are counted from the average last spring frost (May 2) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.
| Crop | When |
|---|---|
| Tomatoes | Start seeds indoors: Mar 7 – Mar 21 Transplant outdoors: May 9 – May 16 |
| Peppers | Start seeds indoors: Feb 21 – Mar 7 Transplant outdoors: May 16 – May 23 |
| Eggplant | Start seeds indoors: Feb 21 – Mar 7 Transplant outdoors: May 16 – May 23 |
| Broccoli | Start seeds indoors: Feb 21 – Mar 7 Transplant outdoors: Apr 4 – Apr 18 |
| Cabbage | Start seeds indoors: Feb 21 – Mar 7 Transplant outdoors: Apr 4 – Apr 18 |
| Onions (sets) | Plant outdoors: Apr 4 – Apr 18 |
| Peas | Sow outdoors: Mar 21 – Apr 4 |
| Spinach | Sow outdoors: Mar 21 – Apr 4 |
| Lettuce | Sow outdoors: Apr 4 – Apr 18 |
| Carrots | Sow outdoors: Apr 4 – Apr 18 |
| Potatoes | Plant outdoors: Apr 4 – Apr 18 |
| Beans | Sow outdoors: May 9 – May 16 |
| Sweet corn | Sow outdoors: May 9 – May 16 |
| Cucumbers | Sow outdoors: May 9 – May 16 |
| Squash & zucchini | Sow outdoors: May 9 – May 16 |
| Basil | Start seeds indoors: Mar 21 – Apr 4 Transplant outdoors: May 9 – May 16 |
Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Aug 18 (8 weeks before the average first fall frost on Oct 13).
Useful for zone 5b gardens
- Seed starting kit with dome — to start seeds indoors before the last frost
- LED grow light for seedlings — stops leggy seedlings
- Frost cloth / plant covers — for late spring and early fall frosts
- Soil thermometer — warm-season crops need soil above 60°F
- Cold frame / mini greenhouse — adds weeks to a short season
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Frost risk in detail
| 90% chance | 50% chance | 10% chance | |
|---|---|---|---|
| Last 32°F frost in spring is after | Apr 19 | May 2 | May 16 |
| First 32°F frost in fall is before | Oct 30 | Oct 13 | Oct 1 |
How to read it: in spring there is a 10% chance of a frost after May 16, so that is a safe date for tender plants. In fall there is a 10% chance of frost before October 1. A hard freeze (28°F) usually ends around April 18.
Hardiness zone by ZIP code in Gardner
- 01440 zone 5b
Nearby cities
- Fitchburg zone 6a, last frost May 1
- Leominster zone 6a, last frost Apr 29
- Holden zone 6b, last frost Apr 23
- Leicester zone 6b, last frost Apr 23
- Worcester zone 6a, last frost Apr 23
- Shrewsbury zone 6a, last frost Apr 23
- Auburn zone 6a, last frost Apr 23
- Charlton zone 6b, last frost May 1
Questions
What growing zone is Gardner, MA?
Gardner is in USDA Plant Hardiness Zone 5b (average extreme winter low -15°F to -10°F), according to the USDA 2023 map.
When is the last frost in Gardner?
The average last spring frost (32°F) in Gardner is May 2. There is still a 10% chance of frost until May 16.
When can I plant tomatoes in Gardner?
Transplant tomatoes outdoors 1–2 weeks after the average last frost: around May 9 – May 16. Start seeds indoors 6–8 weeks before the last frost.
Frost dates: NOAA U.S. Climate Normals 1991–2020, station Ashburnham, MA (USC00190190), 8.2 km (5.1 mi) from the city center, elevation 338 m, based on 11 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.