Frost Report

All states New Hampshire

Frost dates for Berlin, 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 14

typical year

Safe to plant

May 30

frost is over in 9 of 10 years

First fall frost

September 30

typical year

Growing season

135 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 – Apr 16 – 30 –
Spinach – Apr 2 – 23 Aug 5 – 19
Lettuce – Apr 16 – May 7 Aug 5 – 19
Radishes – Apr 16 – May 28 Aug 19 – Sep 2
Onions – Apr 16 – 30 –
Potatoes – Apr 23 – May 7 –
Carrots – Apr 23 – May 14 Jul 8 – 22
Beets – Apr 16 – 30 Jul 22 – Aug 5
Kale Mar 5 – 19 Apr 16 – 30 Jul 22 – Aug 5
Broccoli Mar 5 – 19 Apr 30 – May 14 Jul 22 – Aug 5
Cabbage Feb 19 – Mar 5 Apr 16 – 30 Jul 22 – Aug 5
Garlic – – Aug 19 – Sep 9
Warm-season crops
Tomatoes Apr 4 – 18 May 30 – Jun 13 –
Peppers Mar 28 – Apr 11 Jun 6 – 20 –
Cucumbers – May 30 – Jun 20 –
Zucchini – May 30 – Jun 27 –
Pumpkins – May 30 – Jun 20 –
Green beans – May 30 – Jul 22 –
Sweet corn – May 30 – Jun 27 –
Basil Apr 25 – May 9 Jun 6 – 13 –

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 May 30May 14April 30
Fall frost before September 15September 30October 11

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 April 30 (May 14 in a late year), and the first one in fall around October 10.

Where these dates come from

NOAA weather station BERLIN, NH US (USC00270690), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 4 miles:

03570

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