Frost dates for 94954Petaluma, CA
The average last spring frost in Petaluma is February 28 and the average first fall frost is November 25, giving a typical growing season of about 271 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Feb 28
- Average first fall frost
- Nov 25
- Growing season
- 271 days
Safer after Apr 6 (1-in-10 risk)
Possible by Nov 9 (1-in-10 risk)
First frost typically in 24 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) | Mar 7 · Apr 6 · Apr 27 | Oct 27 · Nov 10 · Nov 28 | 218 days | 100% |
| Frost / freeze (32°F) | Jan 24 · Feb 28 · Apr 6 | Nov 9 · Nov 25 · Dec 16 | 271 days | 100% |
| Hard freeze (28°F) | Dec 17 · Jan 17 · Feb 24 | Nov 20 · Dec 9 · Jan 12 | 331 days | 88% |
Planting calendar for Petaluma
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 | Jan 28 – Apr 5 |
| Tomatoes | Transplant outdoors | Mar 16 – Aug 5 |
| Peppers | Start seeds indoors | Jan 28 – Feb 28 |
| Peppers | Transplant outdoors | Mar 30 – Apr 30 |
| Eggplant | Start seeds indoors | Feb 14 – Mar 15 |
| Eggplant | Transplant outdoors | Mar 30 – Apr 30 |
| Cucumbers | Sow outdoors | Mar 30 – Aug 15 |
| Summer squash | Sow outdoors | Mar 16 – Apr 30 |
| Winter squash & pumpkins | Sow outdoors | Mar 30 – Apr 30 |
| Snap beans | Sow outdoors | Mar 16 – Sep 7 |
| Sweet corn | Sow outdoors | Mar 16 – Aug 5 |
| Watermelon & cantaloupe | Sow outdoors | Mar 30 – Apr 30 |
| Okra | Sow outdoors | Mar 23 – Apr 15 |
| Peas | Sow outdoors (spring) | Jan 28 – Mar 15 |
| Potatoes | Plant outdoors (spring) | Jan 28 – Mar 30 |
| Onions | Start seeds indoors (spring) | Dec 17 – Jan 13 |
| Onions | Transplant outdoors (spring) | Feb 14 – Mar 15 |
| Broccoli | Start seeds indoors (spring) | Jan 10 – Feb 13 |
| Broccoli | Transplant outdoors (spring) | Feb 14 – Mar 15 |
| Broccoli | Start seeds indoors (fall) | Jul 26 – Aug 5 |
| Broccoli | Transplant outdoors (fall) | Aug 25 – Sep 5 |
| Cabbage | Start seeds indoors (spring) | Dec 31 – Jan 28 |
| Cabbage | Transplant outdoors (spring) | Jan 28 – Feb 28 |
| Cabbage | Start seeds indoors (fall) | Jul 16 – Aug 15 |
| Cabbage | Transplant outdoors (fall) | Aug 15 – Sep 15 |
| Leaf lettuce | Sow outdoors (spring) | Jan 28 – Apr 15 |
| Leaf lettuce | Sow outdoors (fall) | Aug 15 – Oct 1 |
| Spinach | Sow outdoors (spring) | Jan 21 – Mar 6 |
| Spinach | Sow outdoors (fall) | Sep 1 – Oct 6 |
| Radishes | Sow outdoors (spring) | Jan 28 – Mar 20 |
| Radishes | Sow outdoors (fall) | Aug 15 – Oct 16 |
| Kale | Sow outdoors (spring) | Feb 14 – Mar 6 |
| Kale | Sow outdoors (fall) | Aug 8 – Sep 15 |
| Carrots | Sow outdoors (spring) | Feb 28 – Apr 15 |
| Carrots | Sow outdoors (fall) | Jul 16 – Aug 31 |
| Garlic | Plant outdoors (fall) | Nov 15 – Dec 16 |
Where these dates come from
ZIP code 94954 is matched to the NOAA station Petaluma Ap, CA, 1 km away, at 20 ft elevation (29 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Petaluma Ap, CA (used) | 20 ft | Feb 28 | Nov 25 |
| Sonoma, CA | 97 ft | Mar 2 | Nov 27 |
| Santa Rosa, CA | 166 ft | Feb 25 | Dec 1 |
| San Rafael Civic Ctr, CA | 120 ft | Jan 11 | Dec 21 |
Frost dates near Petaluma
- Petaluma, CA 94953 · last Feb 28, first Nov 25
- Penngrove, CA 94951 · last Feb 28, first Nov 25
- Cotati, CA 94931 · last Feb 28, first Nov 25
- Novato, CA 94948 · last Feb 28, first Nov 25
- Rohnert Park, CA 94926 · last Feb 25, first Dec 1
- El Verano, CA 95433 · last Mar 2, first Nov 27
- Sonoma, CA 95476 · last Mar 2, first Nov 27
- Boyes Hot Springs, CA 95416 · last Mar 2, first Nov 27
Frequently asked questions
- When is the last frost in Petaluma, CA?
- For ZIP code 94954, the average last spring frost (32°F) is February 28, based on NOAA 1991-2020 climate normals for the Petaluma Ap, CA weather station. There is a 1-in-10 chance of a frost after April 6.
- When is the first frost in Petaluma, CA?
- The average first fall frost (32°F) is November 25. There is a 1-in-10 chance of frost by November 9, so tender plants are at risk from that point on.
- How long is the growing season in 94954?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 271 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.