When to Plant Tomatoes in New Hampshire
America's favorite garden vegetable (technically a fruit). Nothing beats a sun-warmed tomato straight off the vine.
The Short Answer
New Hampshire Frost Dates
Your planting dates depend on which part of New Hampshire you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern New Hampshire | 3b, 4a, 4b | May 20 - Jun 5 | Sep 10 - Sep 25 |
| Southern New Hampshire | 5a, 5b, 6a | May 1 - May 20 | Sep 25 - Oct 10 |
Tomatoes Planting Schedule for New Hampshire
Northern New Hampshire (Zones 3b, 4a, 4b)
Average last frost: May 20 - Jun 5 · Average first frost: Sep 10 - Sep 25
Southern New Hampshire (Zones 5a, 5b, 6a)
Average last frost: May 1 - May 20 · Average first frost: Sep 25 - Oct 10
Growing Tomatoes in New Hampshire
Tomatoes in New Hampshire's Climate
In cold climates with 120-160 frost-free days, tomatoes demand an aggressive indoor start 6-8 weeks before your last frost. Choose short-season varieties that mature in 55-65 days — Stupice, Sub Arctic Plenty, and Glacier are bred for regions exactly like yours. Black plastic mulch can raise soil temperature by 10-15°F, and floating row cover over transplants during cool June nights adds critical warmth. Your goal is getting ripe tomatoes before September frost — every warm day counts.
Soil Considerations for New Hampshire
Rocky, acidic New England soils. Glacial deposits. Granite bedrock. Raised beds essential in many areas. Make sure soil has warmed to at least 60°F before planting tomatoes outside.
New Hampshire Climate & Growing Season
Short growing season especially in north. Cold winters. Cool summers. Hardy varieties important. Tomatoes cannot tolerate any frost, so wait until all frost danger has passed before transplanting outside. Watch local forecasts carefully in spring.
Growing season length varies across New Hampshire: Northern New Hampshire (3b, 4a, 4b) has a last frost around May 20 - Jun 5, while Southern New Hampshire (5a, 5b, 6a) sees frost end around May 1 - May 20. This difference matters for tomatoes — transplant timing shifts by several weeks across the state.
Growing Tips
Pinch off suckers for indeterminate varieties. Stake or cage for best results. Water at the base, not overhead, to prevent blight.
Companion Planting
Plant tomatoes alongside these companions for better growth:
Keep tomatoes away from:
The Bottom Line
Last reviewed: March 29, 2026