Frost dates for 93440Los Alamos, CA
The average last spring frost in Los Alamos is April 11 and the average first fall frost is November 8, giving a typical growing season of about 209 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 11
- Average first fall frost
- Nov 8
- Growing season
- 209 days
Safer after May 6 (1-in-10 risk)
Possible by Oct 14 (1-in-10 risk)
First frost typically in 12 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) | Apr 19 · May 12 · Jun 7 | Sep 21 · Oct 17 · Nov 4 | 154 days | 100% |
| Frost / freeze (32°F) | Mar 14 · Apr 11 · May 6 | Oct 14 · Nov 8 · Nov 29 | 209 days | 100% |
| Hard freeze (28°F) | Jan 24 · Feb 27 · Apr 4 | Nov 7 · Nov 27 · Dec 17 | 271 days | 100% |
Planting calendar for Los Alamos
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 | Mar 11 – May 17 |
| Tomatoes | Transplant outdoors | Apr 27 – Jul 19 |
| Peppers | Start seeds indoors | Mar 11 – Apr 11 |
| Peppers | Transplant outdoors | May 11 – Jun 11 |
| Eggplant | Start seeds indoors | Mar 28 – Apr 26 |
| Eggplant | Transplant outdoors | May 11 – Jun 11 |
| Cucumbers | Sow outdoors | May 11 – Jul 29 |
| Summer squash | Sow outdoors | Apr 27 – Jun 11 |
| Winter squash & pumpkins | Sow outdoors | May 11 – Jun 11 |
| Snap beans | Sow outdoors | Apr 27 – Aug 21 |
| Sweet corn | Sow outdoors | Apr 27 – Jul 19 |
| Watermelon & cantaloupe | Sow outdoors | May 11 – Jun 11 |
| Okra | Sow outdoors | May 4 – May 27 |
| Peas | Sow outdoors (spring) | Mar 11 – Apr 26 |
| Potatoes | Plant outdoors (spring) | Mar 11 – May 11 |
| Onions | Start seeds indoors (spring) | Jan 28 – Feb 24 |
| Onions | Transplant outdoors (spring) | Mar 28 – Apr 26 |
| Broccoli | Start seeds indoors (spring) | Feb 21 – Mar 27 |
| Broccoli | Transplant outdoors (spring) | Mar 28 – Apr 26 |
| Broccoli | Start seeds indoors (fall) | Jul 9 – Jul 19 |
| Broccoli | Transplant outdoors (fall) | Aug 8 – Aug 19 |
| Cabbage | Start seeds indoors (spring) | Feb 11 – Mar 11 |
| Cabbage | Transplant outdoors (spring) | Mar 11 – Apr 11 |
| Cabbage | Start seeds indoors (fall) | Jun 29 – Jul 29 |
| Cabbage | Transplant outdoors (fall) | Jul 29 – Aug 29 |
| Leaf lettuce | Sow outdoors (spring) | Mar 11 – May 27 |
| Leaf lettuce | Sow outdoors (fall) | Jul 29 – Sep 14 |
| Spinach | Sow outdoors (spring) | Mar 4 – Apr 17 |
| Spinach | Sow outdoors (fall) | Aug 15 – Sep 19 |
| Radishes | Sow outdoors (spring) | Mar 11 – May 1 |
| Radishes | Sow outdoors (fall) | Jul 29 – Sep 29 |
| Kale | Sow outdoors (spring) | Mar 28 – Apr 17 |
| Kale | Sow outdoors (fall) | Jul 22 – Aug 29 |
| Carrots | Sow outdoors (spring) | Apr 11 – May 27 |
| Carrots | Sow outdoors (fall) | Jun 29 – Aug 14 |
| Garlic | Plant outdoors (fall) | Oct 29 – Nov 29 |
Where these dates come from
ZIP code 93440 is matched to the NOAA station Cachuma Lake, CA, 27.3 km away, at 789 ft elevation (97 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Cachuma Lake, CA (used) | 789 ft | Apr 11 | Nov 8 |
| Lompoc, CA | 75 ft | Jan 20 | Dec 19 |
| Santa Maria Public Ap, CA | 242 ft | Feb 4 | Dec 13 |
| Twitchell Dam, CA | 582 ft | Feb 4 | Dec 4 |
Frost dates near Los Alamos
- Solvang, CA 93463 · last Apr 11, first Nov 8
- Los Olivos, CA 93441 · last Apr 11, first Nov 8
- Buellton, CA 93427 · last Apr 11, first Nov 8
- Santa Ynez, CA 93460 · last Apr 11, first Nov 8
- Santa Maria, CA 93455 · last Feb 4, first Dec 4
- Lompoc, CA 93436 · last Jan 20, first Dec 19
- Casmalia, CA 93429 · last Feb 4, first Dec 13
- Nipomo, CA 93444 · last Feb 4, first Dec 13
Frequently asked questions
- When is the last frost in Los Alamos, CA?
- For ZIP code 93440, the average last spring frost (32°F) is April 11, based on NOAA 1991-2020 climate normals for the Cachuma Lake, CA weather station. There is a 1-in-10 chance of a frost after May 6.
- When is the first frost in Los Alamos, CA?
- The average first fall frost (32°F) is November 8. There is a 1-in-10 chance of frost by October 14, so tender plants are at risk from that point on.
- How long is the growing season in 93440?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 209 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.