Frost Report

All states Connecticut

Frost dates for Hartford, CT

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

April 17

typical year

Safe to plant

May 1

frost is over in 9 of 10 years

First fall frost

October 26

typical year

Growing season

191 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 – Mar 20 – Apr 3 –
Spinach – Mar 6 – 27 Aug 31 – Sep 14
Lettuce – Mar 20 – Apr 10 Aug 31 – Sep 14
Radishes – Mar 20 – May 1 Sep 14 – 28
Onions – Mar 20 – Apr 3 –
Potatoes – Mar 27 – Apr 10 –
Carrots – Mar 27 – Apr 17 Aug 3 – 17
Beets – Mar 20 – Apr 3 Aug 17 – 31
Kale Feb 6 – 20 Mar 20 – Apr 3 Aug 17 – 31
Broccoli Feb 6 – 20 Apr 3 – 17 Aug 17 – 31
Cabbage Jan 23 – Feb 6 Mar 20 – Apr 3 Aug 17 – 31
Garlic – – Sep 14 – Oct 5
Warm-season crops
Tomatoes Mar 6 – 20 May 1 – 15 –
Peppers Feb 27 – Mar 13 May 8 – 22 –
Cucumbers – May 1 – 22 –
Zucchini – May 1 – 29 –
Pumpkins – May 1 – 22 –
Green beans – May 1 – Aug 17 –
Sweet corn – May 1 – 29 –
Basil Mar 27 – Apr 10 May 8 – 15 –

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 1April 17April 1
Fall frost before October 12October 26November 7

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 3 (April 21 in a late year), and the first one in fall around November 5.

Towns that use these dates

This is the nearest NOAA station with frost records for 2 towns.

Hartford, New Britain

Where these dates come from

NOAA weather station HARTFORD BRAINARD FLD, CT US (USW00014752), 1991–2020 climate normals. It's the nearest station for 31 zip codes, all within 19 miles:

06033, 06040, 06042, 06051, 06052, 06053, 06066, 06067, 06073, 06074, 06103, 06105, 06106, 06107, 06108, 06109, 06110, 06111, 06112, 06114, 06117, 06118, 06119, 06120, 06414, 06416, 06424, 06447, 06456, 06469, 06480

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