When to plant tomatoes in Boston, Massachusetts

April 11 – April 25

Transplant outdoors · typical Boston year

Climate basis: NOAA station Boston Logan INTL AP, MA (USW00014739), 3 mi (5 km) from downtown Boston (ZCTA 02108 centroid), elevation 12 ft, on the 1991–2020 climate normals. Transplant tomatoes outdoors from approximately the dates above, anchored to the median last spring 32°F freeze (April 4). One year in ten still freezes after April 17.

Last spring freezeApril 41-in-10 after Apr 17
First fall freezeNovember 91-in-10 before Oct 29
Frost-free season218 daysmedian at 32°F
Hard freeze, 28°Mar 28Nov 21kills even hardy greens
USDA zone7a0 to 5°F winter low not frost timing

The Boston year

Start seeds indoorsFeb 14 – Feb 28
Transplant outdoorsApr 11 – Apr 25
  • indoors under lights
  • in the garden
  • frost-free season
  • 1-in-10 years still freeze to Apr 17
Tomatoes in Boston · freeze context from Boston Logan INTL AP, MA, 1991–2020 normals.

Every method, with its sources

Start seeds indoors

Feb 14 – Feb 28

Sow 6–8 weeks before the outdoor transplant window opens (UNH: time from seed to transplant 6–8 weeks; Missouri G6570: 6–8 weeks in packs). Anchored to the median last spring freeze (Apr 4). University of New Hampshire Extension · University of Missouri Extension

Transplant outdoors

Apr 11 – Apr 25

UNH: safe to set out 1–2 weeks after last frost. Purdue classes tomato as tender — plant after the average last spring frost. Latest-starting rule (UNH) used; span extended to 14 days. Anchored to the median last spring freeze (Apr 4). University of New Hampshire Extension · Purdue University Extension

Direct-sow outdoors

Not calculated

Direct seeding is not recommended timing practice in the cited guides for most U.S. climates; tomatoes are grown from transplants.

Variety assumption: Assumes an average mid-season variety (roughly 65–80 days from transplant).

These windows describe typical years (1991–2020 climate normals), not this year's forecast. Freezes happen outside them — especially in frost pockets, valleys, and urban edges. Watch the forecast before committing tender plants.

This week, not a typical year:
Crop rule sources (3)

Keep exploring