Twain, CA frost dates
Last spring frostMay 18median date
First fall frostOct 8median date
Growing season143 daysfrost-free
Hardiness zone8aZone 8a
How Twain compares
- In 8 years out of 10, the last spring frost in Twain falls between April 30 and June 9, a 40-day window. The first fall frost falls between September 24 and October 24.
- The median last frost is 48 days later than the California median of Mar 31.
- Its 143-day growing season is longer than 13% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 50 days later than the zone 8a median of Mar 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 8a chart.
- The weather station records an average of 159 nights a year at or below 32°F.
- Compared with Chico, CA, 70 km away, the last frost here is 75 days later than there and the growing season is 115 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 30 |
| 50% (median) | May 18 |
| 10% (safe for tender plants) | June 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 24 |
| 50% (median) | October 8 |
| 90% (late) | October 24 |
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 Twain, CA
Twain, CA frost dates — last frost May 18, first frost Oct 8, zone 8a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 20 to May 4
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 23 to Apr 6Transplant outside: May 25 to Jun 8
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Sow outdoors: Apr 20 to May 25Plant for fall: Aug 13 to Sep 10
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 20 to May 4Sow outdoors: Apr 20 to May 4Plant for fall: Jul 30 to Aug 20
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jul 2 to Jul 23
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Plant for fall: Jul 2 to Jul 23
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jul 2 to Jul 23
Start indoors: Apr 6 to Apr 20Transplant outside: Jun 8 to Jun 22Sow outdoors: Jun 8 to Jun 22
Start indoors: Apr 6 to Apr 20Transplant outside: May 25 to Jun 8
Sow outdoors: Apr 6 to Apr 27Plant for fall: Jul 16 to Aug 6
Sow outdoors: Apr 6 to Apr 27Plant for fall: Aug 13 to Sep 3
Sow outdoors: Apr 13 to May 25Plant for fall: Aug 27 to Sep 17
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 8Sow outdoors: May 25 to Jun 8Plant for fall: Jul 23 to Aug 6
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8Plant for fall: Jul 30 to Aug 13
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 15
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 16 to Jul 30
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 30 to Aug 13
Sow outdoors: Apr 27 to May 18
Sow outdoors: May 4 to Jun 1Plant for fall: Jul 30 to Aug 13
Sow outdoors: May 4 to May 25Plant for fall: Aug 13 to Sep 3
Sow outdoors: May 25 to Jun 15Plant for fall: Jul 23 to Aug 6
Sow outdoors: May 25 to Jun 8
Transplant outside: Jun 1 to Jun 22
Plant for fall: Sep 24 to Oct 29
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Twain, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 23 – Mar 9 | Apr 20 – May 4 | — | — |
| Peppers | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Eggplant | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Tomatoes | Mar 23 – Apr 6 | May 25 – Jun 8 | — | — |
| Lettuce | Mar 23 – Apr 6 | Apr 27 – May 11 | Apr 20 – May 25 | Aug 13 – Sep 10 |
| Kale | Mar 23 – Apr 6 | Apr 20 – May 4 | Apr 20 – May 4 | Jul 30 – Aug 20 |
| Broccoli | Mar 23 – Apr 6 | May 4 – May 18 | — | Jul 2 – Jul 23 |
| Cabbage | Mar 23 – Apr 6 | Apr 27 – May 11 | — | Jul 2 – Jul 23 |
| Cauliflower | Mar 23 – Apr 6 | May 4 – May 18 | — | Jul 2 – Jul 23 |
| Okra | Apr 6 – Apr 20 | Jun 8 – Jun 22 | Jun 8 – Jun 22 | — |
| Basil | Apr 6 – Apr 20 | May 25 – Jun 8 | — | — |
| Peas | — | — | Apr 6 – Apr 27 | Jul 16 – Aug 6 |
| Spinach | — | — | Apr 6 – Apr 27 | Aug 13 – Sep 3 |
| Radishes | — | — | Apr 13 – May 25 | Aug 27 – Sep 17 |
| Cucumbers | Apr 20 – Apr 27 | Jun 1 – Jun 8 | May 25 – Jun 8 | Jul 23 – Aug 6 |
| Zucchini & Summer Squash | Apr 20 – Apr 27 | — | May 25 – Jun 8 | Jul 30 – Aug 13 |
| Winter Squash & Pumpkins | Apr 20 – Apr 27 | — | May 25 – Jun 8 | — |
| Melons & Watermelon | Apr 20 – Apr 27 | Jun 1 – Jun 15 | — | — |
| Carrots | — | — | Apr 27 – May 25 | Jul 16 – Jul 30 |
| Beets | — | — | Apr 27 – May 25 | Jul 30 – Aug 13 |
| Potatoes | — | — | Apr 27 – May 18 | — |
| Swiss Chard | — | — | May 4 – Jun 1 | Jul 30 – Aug 13 |
| Cilantro | — | — | May 4 – May 25 | Aug 13 – Sep 3 |
| Green Beans | — | — | May 25 – Jun 15 | Jul 23 – Aug 6 |
| Sweet Corn | — | — | May 25 – Jun 8 | — |
| Sweet Potatoes | — | Jun 1 – Jun 22 | — | — |
| Garlic | — | — | — | Sep 24 – Oct 29 |
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 Canyon Dam, CA weather station, 14 km away (elevation 4,560 ft (1,390 m)).
Frost dates near Twain
- Belden May 18 · Oct 8
- Meadow Valley May 22 · Sep 25
- Crescent Mills May 22 · Sep 25
- Quincy May 22 · Sep 25
- Storrie Apr 17 · Nov 11
- Greenville May 18 · Oct 8
- Chester May 28 · Sep 28
- Westwood May 18 · Oct 8
- Taylorsville May 22 · Sep 25
- Stirling City Apr 17 · Nov 11
Frequently asked questions
When is the last frost in Twain, CA?
The median last spring frost in Twain, CA is May 18. There is still about a 10% chance of frost after June 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Twain, CA?
The median first fall frost is October 8, with about a 10% chance of frost before September 24.
How long is the growing season in Twain, CA?
About 143 days between the median last spring frost and first fall frost.
What planting zone is Twain, CA?
Twain, CA is in USDA hardiness zone 8a.