Frost dates for 08807Bridgewater, NJ
The average last spring frost in Bridgewater is April 30 and the average first fall frost is October 20, giving a typical growing season of about 172 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 30
- Average first fall frost
- Oct 20
- Growing season
- 172 days
Safer after May 14 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 178 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 27 · May 10 · May 24 | Sep 28 · Oct 9 · Oct 24 | 150 days | 100% |
| Frost / freeze (32°F) | Apr 15 · Apr 30 · May 14 | Oct 5 · Oct 20 · Nov 3 | 172 days | 100% |
| Hard freeze (28°F) | Apr 1 · Apr 15 · May 1 | Oct 15 · Oct 31 · Nov 12 | 198 days | 100% |
Planting calendar for Bridgewater
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 30 – Jun 5 |
| Tomatoes | Transplant outdoors | May 16 – Jun 30 |
| Peppers | Start seeds indoors | Mar 30 – Apr 30 |
| Peppers | Transplant outdoors | May 30 – Jun 30 |
| Eggplant | Start seeds indoors | Apr 16 – May 15 |
| Eggplant | Transplant outdoors | May 30 – Jun 30 |
| Cucumbers | Sow outdoors | May 30 – Jul 10 |
| Summer squash | Sow outdoors | May 16 – Jun 30 |
| Winter squash & pumpkins | Sow outdoors | May 30 – Jun 30 |
| Snap beans | Sow outdoors | May 16 – Aug 2 |
| Sweet corn | Sow outdoors | May 16 – Jun 30 |
| Watermelon & cantaloupe | Sow outdoors | May 30 – Jun 30 |
| Okra | Sow outdoors | May 23 – Jun 15 |
| Peas | Sow outdoors (spring) | Mar 30 – May 15 |
| Potatoes | Plant outdoors (spring) | Mar 30 – May 30 |
| Onions | Start seeds indoors (spring) | Feb 16 – Mar 15 |
| Onions | Transplant outdoors (spring) | Apr 16 – May 15 |
| Broccoli | Start seeds indoors (spring) | Mar 12 – Apr 15 |
| Broccoli | Transplant outdoors (spring) | Apr 16 – May 15 |
| Broccoli | Start seeds indoors (fall) | Jun 20 – Jun 30 |
| Broccoli | Transplant outdoors (fall) | Jul 20 – Jul 31 |
| Cabbage | Start seeds indoors (spring) | Mar 2 – Mar 30 |
| Cabbage | Transplant outdoors (spring) | Mar 30 – Apr 30 |
| Cabbage | Start seeds indoors (fall) | Jun 10 – Jul 10 |
| Cabbage | Transplant outdoors (fall) | Jul 10 – Aug 10 |
| Leaf lettuce | Sow outdoors (spring) | Mar 30 – Jun 15 |
| Leaf lettuce | Sow outdoors (fall) | Jul 10 – Aug 26 |
| Spinach | Sow outdoors (spring) | Mar 23 – May 6 |
| Spinach | Sow outdoors (fall) | Jul 27 – Aug 31 |
| Radishes | Sow outdoors (spring) | Mar 30 – May 20 |
| Radishes | Sow outdoors (fall) | Jul 10 – Sep 10 |
| Kale | Sow outdoors (spring) | Apr 16 – May 6 |
| Kale | Sow outdoors (fall) | Jul 3 – Aug 10 |
| Carrots | Sow outdoors (spring) | Apr 30 – Jun 15 |
| Carrots | Sow outdoors (fall) | Jun 10 – Jul 26 |
| Garlic | Plant outdoors (fall) | Oct 10 – Nov 10 |
Where these dates come from
ZIP code 08807 is matched to the NOAA station Somerville 4 Nw, NJ, 3.6 km away, at 134 ft elevation (35 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Somerville 4 Nw, NJ (used) | 134 ft | Apr 30 | Oct 20 |
| Somerville Somerset Ap, NJ | 105 ft | Apr 26 | Oct 18 |
| Plainfield, NJ | 90 ft | Apr 11 | Oct 28 |
| Wertsville 4 Ne, NJ | 283 ft | Apr 16 | Oct 27 |
Frost dates near Bridgewater
- Raritan, NJ 08869 · last Apr 30, first Oct 20
- Somerville, NJ 08876 · last Apr 26, first Oct 18
- Pluckemin, NJ 07978 · last Apr 30, first Oct 20
- Martinsville, NJ 08836 · last Apr 30, first Oct 20
- Manville, NJ 08835 · last Apr 30, first Oct 20
- Zarephath, NJ 08890 · last Apr 30, first Oct 20
- Bedminster, NJ 07921 · last Apr 30, first Oct 20
- Bound Brook, NJ 08805 · last Apr 30, first Oct 20
Frequently asked questions
- When is the last frost in Bridgewater, NJ?
- For ZIP code 08807, the average last spring frost (32°F) is April 30, based on NOAA 1991-2020 climate normals for the Somerville 4 Nw, NJ weather station. There is a 1-in-10 chance of a frost after May 14.
- When is the first frost in Bridgewater, NJ?
- The average first fall frost (32°F) is October 20. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 08807?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 172 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.