Wrentham, MA planting zone & frost dates

Wrentham is in USDA hardiness zone 6b. The last spring frost usually comes around April 30 and the first fall frost around October 9, for a growing season of about 162 days.

USDA hardiness zone6bavg. extreme winter low -5°F to 0°F

Average last spring frostApril 3090% chance of no frost after May 14

Average first fall frostOctober 910% chance of frost by September 29

Growing season162 daysfrost-free days in an average year

Planting calendar for Wrentham

Dates are counted from the average last spring frost (April 30) 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 5 – Mar 19 Transplant outdoors: May 7 – May 14
Peppers	Start seeds indoors: Feb 19 – Mar 5 Transplant outdoors: May 14 – May 21
Eggplant	Start seeds indoors: Feb 19 – Mar 5 Transplant outdoors: May 14 – May 21
Broccoli	Start seeds indoors: Feb 19 – Mar 5 Transplant outdoors: Apr 2 – Apr 16
Cabbage	Start seeds indoors: Feb 19 – Mar 5 Transplant outdoors: Apr 2 – Apr 16
Onions (sets)	Plant outdoors: Apr 2 – Apr 16
Peas	Sow outdoors: Mar 19 – Apr 2
Spinach	Sow outdoors: Mar 19 – Apr 2
Lettuce	Sow outdoors: Apr 2 – Apr 16
Carrots	Sow outdoors: Apr 2 – Apr 16
Potatoes	Plant outdoors: Apr 2 – Apr 16
Beans	Sow outdoors: May 7 – May 14
Sweet corn	Sow outdoors: May 7 – May 14
Cucumbers	Sow outdoors: May 7 – May 14
Squash & zucchini	Sow outdoors: May 7 – May 14
Basil	Start seeds indoors: Mar 19 – Apr 2 Transplant outdoors: May 7 – May 14

Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Aug 14 (8 weeks before the average first fall frost on Oct 9).

Useful for zone 6b 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 17	Apr 30	May 14
First 32°F frost in fall is before	Oct 23	Oct 9	Sep 29

How to read it: in spring there is a 10% chance of a frost after May 14, so that is a safe date for tender plants. In fall there is a 10% chance of frost before September 29. A hard freeze (28°F) usually ends around April 16.

Hardiness zone by ZIP code in Wrentham

02093 zone 6b

Nearby cities

Norfolk zone 6b, last frost Apr 27
Franklin zone 6b, last frost Apr 30
North Attleborough Center zone 6b, last frost Apr 27
Medway zone 6b, last frost Apr 30
Mansfield zone 6b, last frost Apr 27
Attleboro zone 6b, last frost Apr 27
Holliston zone 6b, last frost Apr 30
Norton zone 6b, last frost Apr 27

All cities in Massachusetts → · Other zone 6b cities →

Questions

What growing zone is Wrentham, MA?

Wrentham is in USDA Plant Hardiness Zone 6b (average extreme winter low -5°F to 0°F), according to the USDA 2023 map.

When is the last frost in Wrentham?

The average last spring frost (32°F) in Wrentham is April 30. There is still a 10% chance of frost until May 14.

When can I plant tomatoes in Wrentham?

Transplant tomatoes outdoors 1–2 weeks after the average last frost: around May 7 – May 14. Start seeds indoors 6–8 weeks before the last frost.

Frost dates: NOAA U.S. Climate Normals 1991–2020, station West Medway, MA (USC00199316), 11.4 km (7.1 mi) from the city center, elevation 64 m, based on 12 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.