Frost dates for 95448Healdsburg, CA
The average last spring frost in Healdsburg is February 15 and the average first fall frost is December 2, giving a typical growing season of about 292 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Feb 15
- Average first fall frost
- Dec 2
- Growing season
- 292 days
Safer after Mar 17 (1-in-10 risk)
Possible by Nov 14 (1-in-10 risk)
First frost typically in 32 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) | Feb 27 · Mar 29 · Apr 20 | Nov 1 · Nov 16 · Dec 2 | 234 days | 100% |
| Frost / freeze (32°F) | Jan 4 · Feb 15 · Mar 17 | Nov 14 · Dec 2 · Jan 1 | 292 days | 99% |
| Hard freeze (28°F) | Dec 14 · Jan 7 · Feb 2 | Nov 28 · Dec 17 · Jan 12 | 347 days | 70% |
Planting calendar for Healdsburg
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 15 – Mar 23 |
| Tomatoes | Transplant outdoors | Mar 3 – Aug 12 |
| Peppers | Start seeds indoors | Jan 15 – Feb 15 |
| Peppers | Transplant outdoors | Mar 17 – Apr 17 |
| Eggplant | Start seeds indoors | Feb 1 – Mar 2 |
| Eggplant | Transplant outdoors | Mar 17 – Apr 17 |
| Cucumbers | Sow outdoors | Mar 17 – Aug 22 |
| Summer squash | Sow outdoors | Mar 3 – Apr 17 |
| Winter squash & pumpkins | Sow outdoors | Mar 17 – Apr 17 |
| Snap beans | Sow outdoors | Mar 3 – Sep 14 |
| Sweet corn | Sow outdoors | Mar 3 – Aug 12 |
| Watermelon & cantaloupe | Sow outdoors | Mar 17 – Apr 17 |
| Okra | Sow outdoors | Mar 10 – Apr 2 |
| Peas | Sow outdoors (spring) | Jan 15 – Mar 2 |
| Potatoes | Plant outdoors (spring) | Jan 15 – Mar 17 |
| Onions | Start seeds indoors (spring) | Dec 4 – Dec 31 |
| Onions | Transplant outdoors (spring) | Feb 1 – Mar 2 |
| Broccoli | Start seeds indoors (spring) | Dec 28 – Jan 31 |
| Broccoli | Transplant outdoors (spring) | Feb 1 – Mar 2 |
| Broccoli | Start seeds indoors (fall) | Aug 2 – Aug 12 |
| Broccoli | Transplant outdoors (fall) | Sep 1 – Sep 12 |
| Cabbage | Start seeds indoors (spring) | Dec 18 – Jan 15 |
| Cabbage | Transplant outdoors (spring) | Jan 15 – Feb 15 |
| Cabbage | Start seeds indoors (fall) | Jul 23 – Aug 22 |
| Cabbage | Transplant outdoors (fall) | Aug 22 – Sep 22 |
| Leaf lettuce | Sow outdoors (spring) | Jan 15 – Apr 2 |
| Leaf lettuce | Sow outdoors (fall) | Aug 22 – Oct 8 |
| Spinach | Sow outdoors (spring) | Jan 8 – Feb 21 |
| Spinach | Sow outdoors (fall) | Sep 8 – Oct 13 |
| Radishes | Sow outdoors (spring) | Jan 15 – Mar 7 |
| Radishes | Sow outdoors (fall) | Aug 22 – Oct 23 |
| Kale | Sow outdoors (spring) | Feb 1 – Feb 21 |
| Kale | Sow outdoors (fall) | Aug 15 – Sep 22 |
| Carrots | Sow outdoors (spring) | Feb 15 – Apr 2 |
| Carrots | Sow outdoors (fall) | Jul 23 – Sep 7 |
| Garlic | Plant outdoors (fall) | Nov 22 – Dec 23 |
Where these dates come from
ZIP code 95448 is matched to the NOAA station Healdsburg, CA, 1.3 km away, at 177 ft elevation (26 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Healdsburg, CA (used) | 177 ft | Feb 15 | Dec 2 |
| Santa Rosa Sonoma Co Ap, CA | 114 ft | Mar 2 | Nov 20 |
| Graton, CA | 200 ft | Mar 20 | Nov 13 |
| Santa Rosa, CA | 166 ft | Feb 25 | Dec 1 |
Frost dates near Healdsburg
- Windsor, CA 95492 · last Mar 2, first Nov 20
- Geyserville, CA 95441 · last Feb 15, first Dec 2
- Forestville, CA 95436 · last Mar 20, first Nov 13
- Rio Nido, CA 95471 · last Mar 2, first Nov 20
- Fulton, CA 95439 · last Mar 2, first Nov 20
- Guerneville, CA 95446 · last Mar 2, first Nov 20
- Santa Rosa, CA 95403 · last Feb 25, first Dec 1
- Graton, CA 95444 · last Mar 20, first Nov 13
Frequently asked questions
- When is the last frost in Healdsburg, CA?
- For ZIP code 95448, the average last spring frost (32°F) is February 15, based on NOAA 1991-2020 climate normals for the Healdsburg, CA weather station. There is a 1-in-10 chance of a frost after March 17.
- When is the first frost in Healdsburg, CA?
- The average first fall frost (32°F) is December 2. There is a 1-in-10 chance of frost by November 14, so tender plants are at risk from that point on.
- How long is the growing season in 95448?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 292 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.