Last frost date in Morristown, NJ
In Morristown, the last spring frost comes around April 18 in an average year. Wait until May 6 if you want 90% odds of no more frost. The first fall frost usually arrives about October 27, which leaves 189 frost-free days. An early freeze before October 11 happens one year in ten.
- Safe after (10% risk)
- May 6
- Average first frost
- Oct 27
- Frost-free season
- 189 days
- Hard freeze (28°F) ends
- Apr 3
Frost possible in low spots Fri night, low 35°F
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2239°
- FriOct 2335°possible frost
- SatOct 2435°possible frost
- SunOct 2538°
- MonOct 2645°
- TueOct 2744°
- WedOct 2844°
Planting calendar for Morristown
Windows count forward or back from the average frost dates above. Click a crop for dates across New Jersey.
TomatoesApr 25–May 9
PumpkinsMay 2–May 16
SunflowersApr 18–May 9
CucumbersMay 2–May 9
CornApr 25–May 9
Sweet potatoesMay 9–May 23
WatermelonMay 2–May 16
Green beansApr 25–May 16
ZucchiniApr 25–May 9
OkraMay 9–May 23
PeppersMay 2–May 16
BasilApr 25–May 9
Butternut squashApr 25–May 9
CantaloupeMay 2–May 16
EggplantMay 2–May 16
PotatoesMar 21–Apr 4
OnionsMar 7–Mar 28
CarrotsMar 28–May 2
LettuceApr 4–Apr 25
BroccoliMar 21–Apr 4
BeetsMar 21–May 2
PeasMar 7–Mar 21
CabbageMar 21–Apr 4
RadishesMar 14–Apr 25
Brussels sproutsApr 4–Apr 18
SpinachMar 7–Mar 28
CilantroApr 4–Apr 25
KaleMar 21–Apr 4
Collard greensMar 21–Apr 4
TurnipsMar 21–Apr 4
DillApr 18–May 2
CeleryApr 25–May 2
CauliflowerApr 4–Apr 18
LeeksApr 4–Apr 18
Swiss chardApr 4–May 2
ParsleyApr 4–Apr 25
Tulip bulbsOct 13–Nov 17
GarlicOct 6–Nov 10
Daffodil bulbsSep 29–Nov 10
StrawberriesMar 21–Apr 4
AsparagusMar 21–Apr 4Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 3 | Apr 18 | May 6 | Oct 11 | Oct 27 | Nov 10 |
| Hard freeze, 28°F | Mar 19 | Apr 3 | Apr 19 | Oct 22 | Nov 6 | Nov 22 |
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 Canoe Brook (USC00281335) sits 7.4 miles from the center of Morristown at 180 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 Morristown, NJ?
The average last frost date in Morristown is April 18, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 6.
When is the first frost in Morristown?
The first frost in fall usually comes around October 27. One year in ten it arrives before October 11.
How long is the growing season in Morristown?
About 189 days between the average last and first frost.
When should I plant tomatoes in Morristown?
Plant tomato seedlings outside from April 25 to May 9. Start seeds indoors six to eight weeks earlier.
Nearby in New Jersey
- ParsippanyApr 17
- SummitApr 18
- WestfieldApr 11
- North PlainfieldApr 11
- PlainfieldApr 11
- East OrangeApr 4
- RoselleApr 11
- South PlainfieldApr 11
- RahwayApr 11
- NewarkApr 4
- CliftonApr 15
- LindenApr 2