DibbleWhen to plant tomato in Zone 3
In Zone 3, the last spring frost usually passes around May 15 and the first fall frost arrives around September 15, leaving about 123 frost-free days. The windows below are computed from those frost dates, with the same math the Dibble app uses.
Short, cool season. Start most warm crops indoors and protect from late frosts.
Planting windows for tomato in Zone 3
| Task | Window |
|---|---|
| Start seeds indoors | Apr 3 to Apr 17 |
| Transplant | May 22 to Jun 5 |
| Estimated harvest | Aug 5 to Oct 4 |
The harvest estimate counts 75 days to maturity, then a picking window of about 60 days. These windows use typical frost dates for Zone 3; Dibble pins them to your exact ZIP code.
Get reminders for these exact dates
Dibble turns your ZIP code into a full planting calendar and reminds you on the right day. Free to start, no account needed.
How to grow tomato
Start seeds indoors about 6 weeks before your last frost. Harden off and transplant a week or two after frost danger passes, burying the stem deep for strong roots.
Companion plants
Good neighbors for Tomato:
Better kept apart:
Tomato in nearby zones
Keep exploring
Tomato: the full growing guide · The Zone 3 planting calendar · Every crop and zone
Plant at the right time this season
Dibble builds your calendar in under a minute. Free to start, no account needed.
Dates are estimates based on typical frost dates for the zone. Your yard has its own microclimate, so use them as a starting point and adjust as you learn your space.