Clearlake Oaks, CA frost dates
How Clearlake Oaks compares
- In 8 years out of 10, the last spring frost in Clearlake Oaks falls between March 24 and April 30, a 37-day window. The first fall frost falls between October 24 and November 20.
- The median last frost is 10 days later than the California median of Mar 31.
- Its 210-day growing season is longer than 37% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 38 days later than the zone 9a median of Mar 3. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 9a chart.
- The weather station records an average of 72 nights a year at or below 32°F.
- Compared with Santa Rosa, CA, 69 km away, the last frost here is 44 days later than there and the growing season is 69 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 24 |
| 50% (median) | April 10 |
| 10% (safe for tender plants) | April 30 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 24 |
| 50% (median) | November 6 |
| 90% (late) | November 20 |
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 Clearlake Oaks, CA
Clearlake Oaks, CA frost dates — last frost Apr 10, first frost Nov 6, zone 9a. whenisthelastfrost.com
When to plant vegetables in Clearlake Oaks, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 16 – Jan 30 | Mar 13 – Mar 27 | — | — |
| Peppers | Jan 30 – Feb 13 | Apr 24 – May 8 | — | — |
| Eggplant | Jan 30 – Feb 13 | Apr 24 – May 8 | — | — |
| Tomatoes | Feb 13 – Feb 27 | Apr 17 – May 1 | — | — |
| Lettuce | Feb 13 – Feb 27 | Mar 20 – Apr 3 | Mar 13 – Apr 17 | Sep 11 – Oct 9 |
| Kale | Feb 13 – Feb 27 | Mar 13 – Mar 27 | Mar 13 – Mar 27 | Aug 28 – Sep 18 |
| Broccoli | Feb 13 – Feb 27 | Mar 27 – Apr 10 | — | Jul 31 – Aug 21 |
| Cabbage | Feb 13 – Feb 27 | Mar 20 – Apr 3 | — | Jul 31 – Aug 21 |
| Cauliflower | Feb 13 – Feb 27 | Mar 27 – Apr 10 | — | Jul 31 – Aug 21 |
| Okra | Feb 27 – Mar 13 | May 1 – May 15 | May 1 – May 15 | — |
| Basil | Feb 27 – Mar 13 | Apr 17 – May 1 | — | — |
| Peas | — | — | Feb 27 – Mar 20 | Aug 14 – Sep 4 |
| Spinach | — | — | Feb 27 – Mar 20 | Sep 11 – Oct 2 |
| Radishes | — | — | Mar 6 – Apr 17 | Sep 25 – Oct 16 |
| Cucumbers | Mar 13 – Mar 20 | Apr 24 – May 1 | Apr 17 – May 1 | Aug 21 – Sep 4 |
| Zucchini & Summer Squash | Mar 13 – Mar 20 | — | Apr 17 – May 1 | Aug 28 – Sep 11 |
| Winter Squash & Pumpkins | Mar 13 – Mar 20 | — | Apr 17 – May 1 | — |
| Melons & Watermelon | Mar 13 – Mar 20 | Apr 24 – May 8 | — | — |
| Carrots | — | — | Mar 20 – Apr 17 | Aug 14 – Aug 28 |
| Beets | — | — | Mar 20 – Apr 17 | Aug 28 – Sep 11 |
| Potatoes | — | — | Mar 20 – Apr 10 | — |
| Swiss Chard | — | — | Mar 27 – Apr 24 | Aug 28 – Sep 11 |
| Cilantro | — | — | Mar 27 – Apr 17 | Sep 11 – Oct 2 |
| Green Beans | — | — | Apr 17 – May 8 | Aug 21 – Sep 4 |
| Sweet Corn | — | — | Apr 17 – May 1 | — |
| Sweet Potatoes | — | Apr 24 – May 15 | — | — |
| Garlic | — | — | — | Oct 23 – Nov 27 |
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 Clearlake 4 Se, CA weather station, 18 km away (elevation 1,348 ft (411 m)).
Frost dates near Clearlake Oaks
- Glenhaven Apr 10 · Nov 6
- Clearlake Park Apr 10 · Nov 6
- Lucerne Apr 10 · Nov 6
- Clearlake Apr 10 · Nov 6
- Nice Apr 10 · Nov 6
- Kelseyville Apr 10 · Nov 6
- Lower Lake Apr 10 · Nov 6
- Finley Feb 25 · Dec 3
- Lakeport Mar 5 · Nov 21
- Upper Lake Mar 5 · Nov 21
Frequently asked questions
When is the last frost in Clearlake Oaks, CA?
The median last spring frost in Clearlake Oaks, CA is April 10. There is still about a 10% chance of frost after April 30, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Clearlake Oaks, CA?
The median first fall frost is November 6, with about a 10% chance of frost before October 24.
How long is the growing season in Clearlake Oaks, CA?
About 210 days between the median last spring frost and first fall frost.
What planting zone is Clearlake Oaks, CA?
Clearlake Oaks, CA is in USDA hardiness zone 9a.