Last frost date in Trenton, NJ

Average last frost
April 17

Expect the last frost in Trenton around April 17. Frost after May 6 happens in only one year out of ten. The first fall frost usually arrives about October 28, which leaves 192 frost-free days. An early freeze before October 11 happens one year in ten.

Safe after (10% risk)
May 6
Average first frost
Oct 28
Frost-free season
192 days
Hard freeze (28°F) ends
Apr 2
Next 7 nights in Trenton

Frost possible in low spots Fri night, low 34°F

National Weather Service forecast, updated Oct 22, 12:57 UTC

  1. ThuOct 2241°
  2. FriOct 2334°possible frost
  3. SatOct 2435°possible frost
  4. SunOct 2538°
  5. MonOct 2645°
  6. TueOct 2744°
  7. WedOct 2844°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Apr 17First frost Oct 28192 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND192 frost-free days
Frost risk through the year at Trenton State College, 3.6 miles from Trenton.

Planting calendar for Trenton

Windows count forward or back from the average frost dates above. Click a crop for dates across New Jersey.

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
Warm-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
TomatoesApr 24–May 8
PumpkinsMay 1–May 15
SunflowersApr 17–May 8
CucumbersMay 1–May 8
CornApr 24–May 8
Sweet potatoesMay 8–May 22
WatermelonMay 1–May 15
Green beansApr 24–May 15
ZucchiniApr 24–May 8
OkraMay 8–May 22
PeppersMay 1–May 15
BasilApr 24–May 8
Butternut squashApr 24–May 8
CantaloupeMay 1–May 15
EggplantMay 1–May 15
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesMar 20–Apr 3
OnionsMar 6–Mar 27
CarrotsMar 27–May 1
LettuceApr 3–Apr 24
BroccoliMar 20–Apr 3
BeetsMar 20–May 1
PeasMar 6–Mar 20
CabbageMar 20–Apr 3
RadishesMar 13–Apr 24
Brussels sproutsApr 3–Apr 17
SpinachMar 6–Mar 27
CilantroApr 3–Apr 24
KaleMar 20–Apr 3
Collard greensMar 20–Apr 3
TurnipsMar 20–Apr 3
DillApr 17–May 1
CeleryApr 24–May 1
CauliflowerApr 3–Apr 17
LeeksApr 3–Apr 17
Swiss chardApr 3–May 1
ParsleyApr 3–Apr 24
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsOct 14–Nov 18
GarlicOct 7–Nov 11
Daffodil bulbsSep 30–Nov 11
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesMar 20–Apr 3
AsparagusMar 20–Apr 3

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FApr 2Apr 17May 6Oct 11Oct 28Nov 10
Hard freeze, 28°FMar 18Apr 2Apr 17Oct 25Nov 7Nov 24

Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.

Where these numbers come from

NOAA station Trenton State College (USC00288880) sits 3.6 miles from the center of Trenton at 100 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.

Questions

When is the last frost in Trenton, NJ?

The average last frost date in Trenton is April 17, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 6.

When is the first frost in Trenton?

The first frost in fall usually comes around October 28. One year in ten it arrives before October 11.

How long is the growing season in Trenton?

About 192 days between the average last and first frost.

When should I plant tomatoes in Trenton?

Plant tomato seedlings outside from April 24 to May 8. Start seeds indoors six to eight weeks earlier.

Nearby in New Jersey

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