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USDA Hardiness Zone 5b

Frost Dates for 03743 — Claremont, New Hampshire

Averages from Newport, Nh US, the nearest reporting station, 8.1 miles away.

Plant tender crops after May 14, and expect the first autumn freeze around October 1. That leaves about 140 frost-free days.

Last spring frost
May 14

50% probability

First fall frost
October 1

50% probability

Growing season
140 days

frost-free

Hardiness zone
5b

-15 to -10°F annual low

Planting calendar for 03743

What to do and when, based on the frost normals for Claremont, New Hampshire
WhenWhat to do
March 5 – March 19

Start peppers and aubergines indoors

They need eight to ten weeks under lights before they can go out.

March 19 – April 2

Start tomatoes indoors

Six to eight weeks gives a transplant big enough to set fruit early.

April 16 – April 30

Sow peas, spinach, lettuce, radish outdoors

These tolerate light frost and prefer to germinate in cool soil.

May 14 onward

Transplant tomatoes, peppers, basil, squash, cucumbers

The average last freeze has passed — still watch the actual forecast.

by July 9

Sow the autumn crop of carrots, beets and brassicas

They need about twelve weeks to size up before growth stops.

by September 17

Harvest tender crops, or be ready to cover them

A first freeze two weeks early is well within normal variation.

October 1 onward

Plant garlic, mulch beds, lift tender bulbs

Garlic wants a cold spell; bare soil loses structure over winter.

What these dates mean

Wait until after May 14 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Claremont, New Hampshire are past their last freeze. Harvest before October 1, which leaves roughly 140 frost-free days.

ZIP 03743 sits in USDA hardiness zone 5b, meaning the average coldest night of the year falls between -15 to -10°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.

These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.

Other zone 5b ZIP codes in New Hampshire