New Hampshire Planting Guide & Growing Season
New Hampshire is in USDA hardiness zone with a growing season of 145 days. The average last spring frost is May 1 - May 30 and the average first fall frost is Sep 15 - Oct 15.
Growing Conditions in New Hampshire
How New Hampshire Compares
Compare New Hampshire's growing conditions with states that have similar climates.
| State | USDA Zone | Last Frost | First Frost | Season (days) |
|---|---|---|---|---|
| New Hampshire (NH) | May 1 - May 30 | Sep 15 - Oct 15 | 145 | |
| Alabama (AL) | Mar 1 - Apr 1 | Oct 25 - Nov 15 | 220 | |
| Alaska (AK) | May 15 - Jun 15 | Aug 15 - Sep 15 | 105 | |
| Arizona (AZ) | Feb 1 - Apr 15 | Oct 15 - Dec 15 | 270 | |
| Arkansas (AR) | Mar 15 - Apr 15 | Oct 15 - Nov 1 | 210 | |
| California (CA) | Jan 15 - Apr 15 | Oct 15 - Dec 31 | 290 |
Frequently Asked Questions About Gardening in New Hampshire
When should I start seeds indoors in New Hampshire?
In New Hampshire, the average last frost date is May 1 - May 30. Start most seeds indoors 6-8 weeks before this date. The USDA hardiness zone for New Hampshire is undefined, with a growing season of approximately 145 days.
What USDA hardiness zone is New Hampshire?
New Hampshire falls in USDA hardiness zones undefined. This affects which perennial plants will survive winter and influences optimal planting times.
When is the first frost in New Hampshire?
The average first frost date in New Hampshire is Sep 15 - Oct 15. Plan to harvest cold-sensitive crops before this date or protect them with row covers.
How long is the growing season in New Hampshire?
New Hampshire has an average growing season of 145 days, from the last frost (May 1 - May 30) to first frost (Sep 15 - Oct 15). This shorter season requires starting many crops indoors and choosing quick-maturing varieties.
Plan Your Garden
Use our seed starting calculator to get personalized planting dates, or browse all states.