Frost dates for 94558 — Napa, CA
Last spring frostMar 6median date
First fall frostNov 30median date
Growing season269 daysfrost-free
Hardiness zone9bZone 9b
How Napa compares
- In 8 years out of 10, the last spring frost in Napa falls between January 31 and April 6, a 65-day window. The first fall frost falls between November 12 and December 19.
- The median last frost is 25 days earlier than the California median of Mar 31.
- Its 269-day growing season is longer than 67% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 14 days later 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 24 nights a year at or below 32°F.
- Nearby Vacaville, CA, 25 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 31 |
| 50% (median) | March 6 |
| 10% (safe for tender plants) | April 6 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 12 |
| 50% (median) | November 30 |
| 90% (late) | December 19 |
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 94558 — Napa, CA — last frost Mar 6, first frost Nov 30, zone 9b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Dec 12 to Dec 26Transplant outside: Feb 6 to Feb 20
Start indoors: Dec 26 to Jan 9Start indoors: Dec 26 to Jan 9Transplant outside: Mar 20 to Apr 3
Start indoors: Dec 26 to Jan 9Start indoors: Dec 26 to Jan 9Transplant outside: Mar 20 to Apr 3
Start indoors: Jan 9 to Jan 23Transplant outside: Mar 13 to Mar 27
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 13 to Feb 27Sow outdoors: Feb 6 to Mar 13Plant for fall: Oct 5 to Nov 2
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 6 to Feb 20Sow outdoors: Feb 6 to Feb 20Plant for fall: Sep 21 to Oct 12
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 20 to Mar 6Plant for fall: Aug 24 to Sep 14
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 13 to Feb 27Plant for fall: Aug 24 to Sep 14
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 20 to Mar 6Plant for fall: Aug 24 to Sep 14
Start indoors: Jan 23 to Feb 6Transplant outside: Mar 27 to Apr 10Sow outdoors: Mar 27 to Apr 10
Start indoors: Jan 23 to Feb 6Transplant outside: Mar 13 to Mar 27
Sow outdoors: Jan 23 to Feb 13Plant for fall: Sep 7 to Sep 28
Sow outdoors: Jan 23 to Feb 13Plant for fall: Oct 5 to Oct 26
Sow outdoors: Jan 30 to Mar 13Plant for fall: Oct 19 to Nov 9
Start indoors: Feb 6 to Feb 13Transplant outside: Mar 20 to Mar 27Sow outdoors: Mar 13 to Mar 27Plant for fall: Sep 14 to Sep 28
Start indoors: Feb 6 to Feb 13Sow outdoors: Mar 13 to Mar 27Plant for fall: Sep 21 to Oct 5
Start indoors: Feb 6 to Feb 13Sow outdoors: Mar 13 to Mar 27
Start indoors: Feb 6 to Feb 13Transplant outside: Mar 20 to Apr 3
Sow outdoors: Feb 13 to Mar 13Plant for fall: Sep 7 to Sep 21
Sow outdoors: Feb 13 to Mar 13Plant for fall: Sep 21 to Oct 5
Sow outdoors: Feb 13 to Mar 6
Sow outdoors: Feb 20 to Mar 20Plant for fall: Sep 21 to Oct 5
Sow outdoors: Feb 20 to Mar 13Plant for fall: Oct 5 to Oct 26
Sow outdoors: Mar 13 to Apr 3Plant for fall: Sep 14 to Sep 28
Sow outdoors: Mar 13 to Mar 27
Transplant outside: Mar 20 to Apr 10
Plant for fall: Nov 16 to Dec 21
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Napa, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Dec 12 – Dec 26 | Feb 6 – Feb 20 | — | — |
| Peppers | Dec 26 – Jan 9 | Mar 20 – Apr 3 | — | — |
| Eggplant | Dec 26 – Jan 9 | Mar 20 – Apr 3 | — | — |
| Tomatoes | Jan 9 – Jan 23 | Mar 13 – Mar 27 | — | — |
| Lettuce | Jan 9 – Jan 23 | Feb 13 – Feb 27 | Feb 6 – Mar 13 | Oct 5 – Nov 2 |
| Kale | Jan 9 – Jan 23 | Feb 6 – Feb 20 | Feb 6 – Feb 20 | Sep 21 – Oct 12 |
| Broccoli | Jan 9 – Jan 23 | Feb 20 – Mar 6 | — | Aug 24 – Sep 14 |
| Cabbage | Jan 9 – Jan 23 | Feb 13 – Feb 27 | — | Aug 24 – Sep 14 |
| Cauliflower | Jan 9 – Jan 23 | Feb 20 – Mar 6 | — | Aug 24 – Sep 14 |
| Okra | Jan 23 – Feb 6 | Mar 27 – Apr 10 | Mar 27 – Apr 10 | — |
| Basil | Jan 23 – Feb 6 | Mar 13 – Mar 27 | — | — |
| Peas | — | — | Jan 23 – Feb 13 | Sep 7 – Sep 28 |
| Spinach | — | — | Jan 23 – Feb 13 | Oct 5 – Oct 26 |
| Radishes | — | — | Jan 30 – Mar 13 | Oct 19 – Nov 9 |
| Cucumbers | Feb 6 – Feb 13 | Mar 20 – Mar 27 | Mar 13 – Mar 27 | Sep 14 – Sep 28 |
| Zucchini & Summer Squash | Feb 6 – Feb 13 | — | Mar 13 – Mar 27 | Sep 21 – Oct 5 |
| Winter Squash & Pumpkins | Feb 6 – Feb 13 | — | Mar 13 – Mar 27 | — |
| Melons & Watermelon | Feb 6 – Feb 13 | Mar 20 – Apr 3 | — | — |
| Carrots | — | — | Feb 13 – Mar 13 | Sep 7 – Sep 21 |
| Beets | — | — | Feb 13 – Mar 13 | Sep 21 – Oct 5 |
| Potatoes | — | — | Feb 13 – Mar 6 | — |
| Swiss Chard | — | — | Feb 20 – Mar 20 | Sep 21 – Oct 5 |
| Cilantro | — | — | Feb 20 – Mar 13 | Oct 5 – Oct 26 |
| Green Beans | — | — | Mar 13 – Apr 3 | Sep 14 – Sep 28 |
| Sweet Corn | — | — | Mar 13 – Mar 27 | — |
| Sweet Potatoes | — | Mar 20 – Apr 10 | — | — |
| Garlic | — | — | — | Nov 16 – Dec 21 |
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 Markley Cove, CA weather station, 12 km away (elevation 479 ft (146 m)).
ZIP codes in Napa: 94558 94559 94581
Frost dates near Napa
- Yountville Mar 2 · Nov 27
- Oakville Feb 3 · Dec 4
- Rutherford Feb 3 · Dec 4
- Saint Helena Feb 3 · Dec 4
- Angwin Apr 7 · Dec 5
- Deer Park Apr 7 · Dec 5
- Pope Valley Apr 7 · Dec 5
- Vacaville Jan 31 · Dec 11
Frequently asked questions
When is the last frost in Napa, CA?
The median last spring frost in Napa, CA is March 6. There is still about a 10% chance of frost after April 6, 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 November 30, with about a 10% chance of frost before November 12.
How long is the growing season in Napa, CA?
About 269 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.