Massachusetts · zones 5a–7a
When to plant tomatoes in Massachusetts.
Sow or transplant between Apr 29 to Jun 29 in a typical year, keyed to Massachusetts's median last frost around Apr 22. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Tomatoes dates for a typical Massachusetts season.
1 · Start indoors
Mar 18 to May 18
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
Apr 29 to Jun 29
Keyed to the ~Apr 22 last frost. Sow 0.25" deep, 24" apart.
Harvest
~73 days later
~12 lb per plant over ~8 weeks.
Massachusetts spans more than one climate: Zone 6 is the most common zone, but the state runs 5a to 7a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Massachusetts: watch for
The pests that find tomatoes here.
A middle-length season, about 181 frost-free days, means tomato, slicing overlaps tomato hornworm for a stretch each summer. Check plants every week or two and treat early.
Big green caterpillars strip leaves and leave black droppings.
Organic fix: Handpick at dusk; spray Bt on the young ones.
Clusters on new growth, sticky leaves, curling tips.
Organic fix: Blast with water, then insecticidal soap or neem.
Dark spots with concentric rings, starting on the lowest, oldest leaves.
Organic fix: Remove affected leaves, mulch to stop soil splash, space for airflow.
Greasy, water-soaked blotches in cool, wet spells. No rings, and not bottom-up.
Organic fix: Pull infected plants fast, keep leaves dry, use neem as a preventive.
Septoria leaf spot
Many small tan spots with dark brown edges, low leaves first, no rings inside.
Organic fix: Strip the lowest leaves, mulch against soil splash, stake for airflow.
Your season math: Massachusetts gives tomatoes about 181 frost-free days, and it needs roughly 73 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting tomatoes in Massachusetts: questions
When should I plant tomatoes in Massachusetts?+
In a typical Massachusetts year, sow tomatoes or set out transplants between Apr 29 to Jun 29, keyed to the state's median last frost around Apr 22. Your exact dates shift with your ZIP code and microclimate.
When do I start tomatoes seeds indoors in Massachusetts?+
Start seeds inside about 6 weeks before set-out: roughly Mar 18 to May 18 for a typical Massachusetts season.
What USDA zone is Massachusetts?+
Massachusetts spans zones 5a–7a, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many tomatoes plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.