When to plant tomatoes in North Dakota
North Dakota spans USDA hardiness zones 3a-4b. Average last spring frost: 05-25. This calendar gives you the indoor start, transplant, and direct-sow dates for Solanum lycopersicum.
North Dakota planting dates for tomatoes
| Phase | Date in North Dakota | Notes |
|---|---|---|
| Start seeds indoors | March 30 | 8 weeks before last frost |
| Transplant outdoors | June 8 | 2 weeks after last frost |
Why these dates
Tomatoes are warm-season crops that need 6-8 hours of direct sun and soil temperatures above 60F to thrive. Indeterminate varieties need staking or caging. Determinate varieties stay bushier and ripen all at once.
The dates above are anchored to North Dakota's average last spring frost date of 05-25, with offsets standard across university Extension publications. For zone-specific local timing, use the frost date lookup tool with your ZIP code.
More on growing tomatoes
The full growing guide for tomatoes - varieties, soil, fertilization, pests, harvest, storage - is here: Tomatoes growing guide.
More North Dakota planting information
- Full North Dakota planting calendar (all crops + ornamentals)
- Find your exact USDA zone by ZIP
- Look up your average frost dates
- Seed starting timeline calculator