Frost Report

All states New Hampshire

Frost dates for Colebrook, NH

When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.

Last spring frost

May 31

typical year

Safe to plant

June 14

frost is over in 9 of 10 years

First fall frost

September 21

typical year

Growing season

112 days

frost-free, typical year

When to plant

Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.

CropStart indoorsPlant outsideFall planting
Cool-season crops
Peas – May 3 – 17 –
Spinach – Apr 19 – May 10 Jul 27 – Aug 10
Lettuce – May 3 – 24 Jul 27 – Aug 10
Radishes – May 3 – Jun 14 Aug 10 – 24
Onions – May 3 – 17 –
Potatoes – May 10 – 24 –
Carrots – May 10 – 31 Jun 29 – Jul 13
Beets – May 3 – 17 Jul 13 – 27
Kale Mar 22 – Apr 5 May 3 – 17 Jul 13 – 27
Broccoli Mar 22 – Apr 5 May 17 – 31 Jul 13 – 27
Cabbage Mar 8 – 22 May 3 – 17 Jul 13 – 27
Garlic – – Aug 10 – 31
Warm-season crops
Tomatoes Apr 19 – May 3 Jun 14 – 28 –
Peppers Apr 12 – 26 Jun 21 – Jul 5 –
Cucumbers – Jun 14 – Jul 5 –
Zucchini – Jun 14 – Jul 12 –
Pumpkins Season usually too short. Try a quick variety or row covers.
Green beans – Jun 14 – Jul 13 –
Sweet corn – Jun 14 – Jul 12 –
Basil May 10 – 24 Jun 21 – 28 –

Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.

The year at a glance

Start indoors Plant outside Fall planting

The chance of frost, by date

1 year in 10Half of years9 years in 10
Spring frost after June 14May 31May 16
Fall frost before September 7September 21October 2

Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.

Hard freeze (28°F)

A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around May 17 (May 31 in a late year), and the first one in fall around October 1.

Where these dates come from

NOAA weather station COLEBROOK 3SW, NH US (USC00271647), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 8 miles:

03576, 05903

Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.