When to plant in Princeton, NJ
USDA Zone 7aPrinceton, New Jersey frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
In zone 7a, Princeton supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.
Frost probability
HIGHTSTOWN 2 W · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Princeton’s own odds, recorded at HIGHTSTOWN 2 W.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 23 | May 8 | Apr 24 | Sep 26 | Oct 6 | Oct 19 |
| 32°F | May 12 | Apr 25 | Apr 12 | Oct 4 | Oct 16 | Oct 29 |
| 28°F | Apr 26 | Apr 10 | Mar 26 | Oct 13 | Oct 28 | Nov 11 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Princeton, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 14 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Princeton planting FAQ
When is the last spring frost in Princeton, NJ?
Princeton's average last spring frost falls near April 25 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Princeton, NJ?
In Princeton, the first 32°F freeze of fall lands around October 16 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Princeton in?
Princeton is in USDA hardiness zone 7a. In zone 7a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Princeton?
Princeton has about 174 frost-free days — a moderate growing season — between the average last spring frost (April 25) and first fall frost (October 16).
When should I plant tomatoes in Princeton?
For Princeton, sow tomatoes indoors about February 28–March 14 and move the seedlings out around May 2, after the last spring frost.
Never miss a window in Princeton
An email when it’s time to start seeds, transplant, and sow — timed to Princeton’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Princeton Meadows · 9 km
- Kendall Park · 11 km
- Mercerville · 14 km
- Franklin Park · 14 km
- Blackwells Mills · 15 km
- Hamilton Square · 15 km
- Hillsborough · 17 km
- Trenton · 17 km
Frost dates recorded at HIGHTSTOWN 2 W, 13 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Princeton, NJ — Frost Dates & Zone 7a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00283951. Retrieved from https://blissgarden.com/new-jersey/princeton.