Lebanon, NH planting zone & frost dates

Lebanon is in USDA hardiness zone 5a. The last spring frost usually comes around May 9 and the first fall frost around October 6, for a growing season of about 148 days.

USDA hardiness zone5aavg. extreme winter low -20°F to -15°F
Average last spring frostMay 990% chance of no frost after May 24
Average first fall frostOctober 610% chance of frost by September 23
Growing season148 daysfrost-free days in an average year

Planting calendar for Lebanon

Dates are counted from the average last spring frost (May 9) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.

CropWhen
TomatoesStart seeds indoors: Mar 14 – Mar 28
Transplant outdoors: May 16 – May 23
PeppersStart seeds indoors: Feb 28 – Mar 14
Transplant outdoors: May 23 – May 30
EggplantStart seeds indoors: Feb 28 – Mar 14
Transplant outdoors: May 23 – May 30
BroccoliStart seeds indoors: Feb 28 – Mar 14
Transplant outdoors: Apr 11 – Apr 25
CabbageStart seeds indoors: Feb 28 – Mar 14
Transplant outdoors: Apr 11 – Apr 25
Onions (sets)Plant outdoors: Apr 11 – Apr 25
PeasSow outdoors: Mar 28 – Apr 11
SpinachSow outdoors: Mar 28 – Apr 11
LettuceSow outdoors: Apr 11 – Apr 25
CarrotsSow outdoors: Apr 11 – Apr 25
PotatoesPlant outdoors: Apr 11 – Apr 25
BeansSow outdoors: May 16 – May 23
Sweet cornSow outdoors: May 16 – May 23
CucumbersSow outdoors: May 16 – May 23
Squash & zucchiniSow outdoors: May 16 – May 23
BasilStart seeds indoors: Mar 28 – Apr 11
Transplant outdoors: May 16 – May 23

Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Aug 11 (8 weeks before the average first fall frost on Oct 6).

Useful for zone 5a gardens

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Frost risk in detail

90% chance50% chance10% chance
Last 32°F frost in spring is afterApr 27May 9May 24
First 32°F frost in fall is beforeOct 19Oct 6Sep 23

How to read it: in spring there is a 10% chance of a frost after May 24, so that is a safe date for tender plants. In fall there is a 10% chance of frost before September 23. A hard freeze (28°F) usually ends around April 29.

Hardiness zone by ZIP code in Lebanon

Nearby cities

All cities in New Hampshire → · Other zone 5a cities →

Questions

What growing zone is Lebanon, NH?

Lebanon is in USDA Plant Hardiness Zone 5a (average extreme winter low -20°F to -15°F), according to the USDA 2023 map.

When is the last frost in Lebanon?

The average last spring frost (32°F) in Lebanon is May 9. There is still a 10% chance of frost until May 24.

When can I plant tomatoes in Lebanon?

Transplant tomatoes outdoors 1–2 weeks after the average last frost: around May 16 – May 23. Start seeds indoors 6–8 weeks before the last frost.

Frost dates: NOAA U.S. Climate Normals 1991–2020, station Lebanon Muni Ap, NH (USW00094765), 4.6 km (2.9 mi) from the city center, elevation 182 m, based on 22 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.