Frost Dates for Trenton, NJ

In Trenton, NJ, the average last spring frost is around Apr 17 and the average first fall frost around Oct 28, for a growing season of about 192 days. For frost-tender plants, wait until May 6, when the chance of frost drops to 10%.

Average last frostApr 1750% chance of frost after this date
Safe to plantMay 6only a 10% chance of frost after
Average first frostOct 2850% chance of frost before this date
Growing season192 daysfrost-free in an average year

Based on NOAA 1991–2020 records from the Trenton State College, NJ weather station, 4 miles away, elevation 100 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.

Frost probability by date

Chance of a 32°F frost after the spring date, or before the fall date.

ChanceLast spring frostFirst fall frost
10%May 6Oct 11
20%Apr 30Oct 16
30%Apr 25Oct 21
40%Apr 20Oct 24
50%Apr 17Oct 28
60%Apr 14Oct 31
70%Apr 10Nov 2
80%Apr 7Nov 5
90%Apr 2Nov 10

Light frost vs. hard freeze

Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.

TemperatureLast in springFirst in fall
Light frost (36°F)May 1Oct 15
Frost / freeze (32°F)Apr 17Oct 28
Hard freeze (28°F)Apr 2Nov 7

Planting calendar for Trenton

Start indoors Plant outside Fall planting
JanFebMarAprMayJunJulAugSepOctNovDec
Tomatoes
Indoors Feb 20 – Mar 6
Transplant Apr 24 – May 8
Peppers
Indoors Feb 6 – Feb 20
Transplant May 1 – May 15
Eggplant
Indoors Feb 6 – Feb 20
Transplant May 1 – May 15
Basil
Indoors Mar 6 – Mar 20
Transplant Apr 24 – May 8
Cucumbers
Indoors Mar 20 – Mar 27
Sow or transplant Apr 24 – May 8
Zucchini and summer squash
Indoors Mar 20 – Mar 27
Sow or transplant Apr 24 – May 8
Pumpkins and winter squash
Sow Apr 24 – May 8
Watermelons and melons
Indoors Mar 20 – Mar 27
Sow or transplant May 1 – May 15
Green beans
Sow Apr 24 – May 8
Sweet corn
Sow Apr 24 – May 8
Lettuce
Indoors Mar 6 – Mar 20
Sow or transplant Mar 20 – Apr 3
Fall sowing Sep 2 – Sep 30
Spinach
Sow Mar 6 – Mar 27
Fall sowing Sep 2 – Sep 23
Peas
Sow Mar 6 – Mar 20
Fall sowing Aug 19 – Sep 2
Kale
Indoors Feb 20 – Mar 6
Sow or transplant Mar 20 – Apr 3
Fall sowing Aug 19 – Sep 16
Broccoli
Indoors Feb 20 – Mar 6
Transplant Apr 3 – Apr 17
Fall sowing Aug 5 – Aug 19
Cabbage
Indoors Feb 20 – Mar 6
Transplant Mar 27 – Apr 10
Fall sowing Aug 5 – Aug 19
Carrots
Sow Mar 27 – Apr 17
Fall sowing Aug 5 – Aug 19
Radishes
Sow Mar 13 – Apr 3
Fall sowing Sep 16 – Oct 7
Beets
Sow Mar 27 – Apr 17
Fall sowing Aug 19 – Sep 2
Onions (sets or transplants)
Indoors Jan 23 – Feb 6
Plant Mar 20 – Apr 3
Potatoes
Plant Mar 27 – Apr 10
Garlic
Plant Oct 28 – Nov 25

Based on the average last frost (Apr 17) and first frost (Oct 28). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.

Nearby cities

PrincetonNew BrunswickCamdenSayrevilleSouth PlainfieldPlainfieldPerth AmboyRahwayAll New Jersey towns