Frost dates for 94559 — Napa, CA
Last spring frostFeb 12median date
First fall frostDec 4median date
Growing season295 daysfrost-free
Hardiness zone9bZone 9b
How Napa compares
- In 8 years out of 10, the last spring frost in Napa falls between January 3 and March 13, a 69-day window. The first fall frost falls between November 15 and January 4.
- The median last frost is 47 days earlier than the California median of Mar 31.
- Its 295-day growing season is longer than 96% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 8 days earlier than the zone 9b median of Feb 20. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 9b chart.
- The weather station records an average of 13 nights a year at or below 32°F.
- Nearby Fairfield, CA, 18 km away, gets only light, occasional frost, a reminder of how much elevation and distance from the coast matter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | January 3 |
| 50% (median) | February 12 |
| 10% (safe for tender plants) | March 13 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 15 |
| 50% (median) | December 4 |
| 90% (late) | January 4 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Napa, CA
Frost dates for 94559 — Napa, CA — last frost Feb 12, first frost Dec 4, zone 9b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Nov 20 to Dec 4Transplant outside: Jan 15 to Jan 29
Start indoors: Dec 4 to Dec 18Transplant outside: Feb 26 to Mar 12
Start indoors: Dec 4 to Dec 18Transplant outside: Feb 26 to Mar 12
Start indoors: Dec 18 to Jan 1Start indoors: Dec 18 to Jan 1Transplant outside: Feb 19 to Mar 5
Start indoors: Dec 18 to Jan 1Start indoors: Dec 18 to Jan 1Transplant outside: Jan 22 to Feb 5Sow outdoors: Jan 15 to Feb 19Plant for fall: Oct 9 to Nov 6
Start indoors: Dec 18 to Jan 1Start indoors: Dec 18 to Jan 1Transplant outside: Jan 15 to Jan 29Sow outdoors: Jan 15 to Jan 29Plant for fall: Sep 25 to Oct 16
Start indoors: Dec 18 to Jan 1Start indoors: Dec 18 to Jan 1Transplant outside: Jan 29 to Feb 12Plant for fall: Aug 28 to Sep 18
Start indoors: Dec 18 to Jan 1Start indoors: Dec 18 to Jan 1Transplant outside: Jan 22 to Feb 5Plant for fall: Aug 28 to Sep 18
Start indoors: Dec 18 to Jan 1Start indoors: Dec 18 to Jan 1Transplant outside: Jan 29 to Feb 12Plant for fall: Aug 28 to Sep 18
Start indoors: Jan 1 to Jan 15Transplant outside: Mar 5 to Mar 19Sow outdoors: Mar 5 to Mar 19
Start indoors: Jan 1 to Jan 15Transplant outside: Feb 19 to Mar 5
Sow outdoors: Jan 1 to Jan 22Plant for fall: Sep 11 to Oct 2
Sow outdoors: Jan 1 to Jan 22Plant for fall: Oct 9 to Oct 30
Sow outdoors: Jan 8 to Feb 19Plant for fall: Oct 23 to Nov 13
Start indoors: Jan 15 to Jan 22Transplant outside: Feb 26 to Mar 5Sow outdoors: Feb 19 to Mar 5Plant for fall: Sep 18 to Oct 2
Start indoors: Jan 15 to Jan 22Sow outdoors: Feb 19 to Mar 5Plant for fall: Sep 25 to Oct 9
Start indoors: Jan 15 to Jan 22Sow outdoors: Feb 19 to Mar 5
Start indoors: Jan 15 to Jan 22Transplant outside: Feb 26 to Mar 12
Sow outdoors: Jan 22 to Feb 19Plant for fall: Sep 11 to Sep 25
Sow outdoors: Jan 22 to Feb 19Plant for fall: Sep 25 to Oct 9
Sow outdoors: Jan 22 to Feb 12
Sow outdoors: Jan 29 to Feb 26Plant for fall: Sep 25 to Oct 9
Sow outdoors: Jan 29 to Feb 19Plant for fall: Oct 9 to Oct 30
Sow outdoors: Feb 19 to Mar 12Plant for fall: Sep 18 to Oct 2
Sow outdoors: Feb 19 to Mar 5
Transplant outside: Feb 26 to Mar 19
Plant for fall: Nov 20 to Dec 25
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Napa, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Nov 20 – Dec 4 | Jan 15 – Jan 29 | — | — |
| Peppers | Dec 4 – Dec 18 | Feb 26 – Mar 12 | — | — |
| Eggplant | Dec 4 – Dec 18 | Feb 26 – Mar 12 | — | — |
| Tomatoes | Dec 18 – Jan 1 | Feb 19 – Mar 5 | — | — |
| Lettuce | Dec 18 – Jan 1 | Jan 22 – Feb 5 | Jan 15 – Feb 19 | Oct 9 – Nov 6 |
| Kale | Dec 18 – Jan 1 | Jan 15 – Jan 29 | Jan 15 – Jan 29 | Sep 25 – Oct 16 |
| Broccoli | Dec 18 – Jan 1 | Jan 29 – Feb 12 | — | Aug 28 – Sep 18 |
| Cabbage | Dec 18 – Jan 1 | Jan 22 – Feb 5 | — | Aug 28 – Sep 18 |
| Cauliflower | Dec 18 – Jan 1 | Jan 29 – Feb 12 | — | Aug 28 – Sep 18 |
| Okra | Jan 1 – Jan 15 | Mar 5 – Mar 19 | Mar 5 – Mar 19 | — |
| Basil | Jan 1 – Jan 15 | Feb 19 – Mar 5 | — | — |
| Peas | — | — | Jan 1 – Jan 22 | Sep 11 – Oct 2 |
| Spinach | — | — | Jan 1 – Jan 22 | Oct 9 – Oct 30 |
| Radishes | — | — | Jan 8 – Feb 19 | Oct 23 – Nov 13 |
| Cucumbers | Jan 15 – Jan 22 | Feb 26 – Mar 5 | Feb 19 – Mar 5 | Sep 18 – Oct 2 |
| Zucchini & Summer Squash | Jan 15 – Jan 22 | — | Feb 19 – Mar 5 | Sep 25 – Oct 9 |
| Winter Squash & Pumpkins | Jan 15 – Jan 22 | — | Feb 19 – Mar 5 | — |
| Melons & Watermelon | Jan 15 – Jan 22 | Feb 26 – Mar 12 | — | — |
| Carrots | — | — | Jan 22 – Feb 19 | Sep 11 – Sep 25 |
| Beets | — | — | Jan 22 – Feb 19 | Sep 25 – Oct 9 |
| Potatoes | — | — | Jan 22 – Feb 12 | — |
| Swiss Chard | — | — | Jan 29 – Feb 26 | Sep 25 – Oct 9 |
| Cilantro | — | — | Jan 29 – Feb 19 | Oct 9 – Oct 30 |
| Green Beans | — | — | Feb 19 – Mar 12 | Sep 18 – Oct 2 |
| Sweet Corn | — | — | Feb 19 – Mar 5 | — |
| Sweet Potatoes | — | Feb 26 – Mar 19 | — | — |
| Garlic | — | — | — | Nov 20 – Dec 25 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Napa State Hospital, CA weather station, 2 km away (elevation 36 ft (11 m)).
ZIP codes in Napa: 94558 94559 94581
Frost dates near Napa
- Vineburg Mar 2 · Nov 27
- American Canyon Mar 5 · Nov 21
- Yountville Mar 2 · Nov 27
- Sonoma Mar 2 · Nov 27
- Boyes Hot Springs Mar 2 · Nov 27
- El Verano Mar 2 · Nov 27
- Fairfield Jan 15 · Dec 14
- Oakville Feb 3 · Dec 4
Frequently asked questions
When is the last frost in Napa, CA?
The median last spring frost in Napa, CA is February 12. There is still about a 10% chance of frost after March 13, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Napa, CA?
The median first fall frost is December 4, with about a 10% chance of frost before November 15.
How long is the growing season in Napa, CA?
About 295 days between the median last spring frost and first fall frost.
What planting zone is Napa, CA?
Napa, CA is in USDA hardiness zone 9b.