Fall in zone 8aPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 91948 (Mount Laguna, CA)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Mt Laguna #3, CA (3 miles away).
- Average last spring frostApr 2250% chance of a 32°F freeze after this date
- Average first fall frostNov 850% chance of a 32°F freeze by this date
- Growing season (frost-free)197 daysmedian, 32°F threshold
- USDA hardiness zone8a10 to 15°F avg. coldest night
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This week in your yard
As of Oct 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
77°F 55°F or warmer
24-hour average · latest 73°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Fallbrook 5 NE (57 mi).
4-inch depth
78°F 55°F or warmer
24-hour average · latest 76°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Fallbrook 5 NE (57 mi).
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 91948 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 78°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent (annual bluegrass, winter weeds): not yet. Apply as soil cools toward 70°F (typically September to October).
Fertilizer window
Lawn region: California coastal and valleys. Timing only; always follow the product label.
- Bermudagrass (warm-season): Spring: Several weeks after the lawn is fully green (April–May) (about Jun 7 here, using green-up about 3–4 weeks after your average last frost); Summer: Every 4–6 weeks through mid-August (heaviest feeder of the group); Late: Light, low-nitrogen/high-potassium feeding about 4 weeks before first frost, or skip. Avoid: Heavy late-fall nitrogen (linked to spring dead spot).
- Tall fescue (cool-season): Early fall: September (main feeding); Late fall: November, while still green; Late winter: Optional light feeding February–March. Avoid: Feeding after mid-spring and through summer in the transition zone (stress and brown patch).
Plant now
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Nov 8: skip heavy pruning in the 6–8 weeks before it, because new growth may not harden off in time.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | Mar 25 |
| 50% (the "average" last frost) | Apr 22 |
| 10% (cautious: only 1 year in 10 freezes later) | May 21 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Oct 10 |
| 50% (the "average" first frost) | Nov 8 |
| 90% (late: most years have frozen by now) | Dec 4 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 10 | Oct 23 |
| 32°F (freeze) | Apr 22 | Nov 8 |
| 28°F (hard freeze) | Apr 2 | Dec 1 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 91948
Dates count from your average last spring frost (Apr 22) and first fall frost (Nov 8). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Feb 25–Mar 11 | Apr 29–May 13 (transplant) | – |
| Pepper (sweet and hot) | Feb 11–25 | May 6–20 (transplant) | – |
| Eggplant | Feb 11–25 | May 6–20 (transplant) | – |
| Tomatillo | Feb 25–Mar 11 | Apr 29–May 13 (transplant) | – |
| Lettuce | Feb 25–Mar 11 | Apr 1–22 (transplant) Mar 25–May 6 (sow outdoors) | Sep 13–Oct 4 (transplant) Aug 30–Sep 27 (sowing) |
| Spinach | – | Mar 11–Apr 1 (sow outdoors) | Sep 13–Oct 4 (sowing) |
| Kale | Feb 25–Mar 11 | Mar 25–Apr 8 (transplant) Mar 25–Apr 8 (sow outdoors) | Aug 16–Sep 13 (transplant) Aug 2–30 (sowing) |
| Collards | Feb 25–Mar 11 | Mar 25–Apr 22 (transplant) Mar 25–Apr 22 (sow outdoors) | Aug 16–Sep 13 (transplant) Aug 2–30 (sowing) |
| Broccoli | Feb 11–25 | Mar 25–Apr 8 (transplant) | Aug 2–30 (transplant) |
| Cabbage | Feb 11–25 | Mar 25–Apr 8 (transplant) | Aug 2–30 (transplant) |
| Cauliflower | Feb 11–25 | Apr 8–22 (transplant) | Aug 2–30 (transplant) |
| Brussels sprouts | Jan 28–Feb 11 | Mar 25–Apr 8 (transplant) | Jul 19–Aug 9 (transplant) |
| Kohlrabi | Feb 25–Mar 11 | Mar 25–Apr 8 (transplant) Mar 25–Apr 8 (sow outdoors) | Aug 30–Sep 13 (sowing) |
| Bok choy / Asian greens | – | Mar 25–Apr 8 (sow outdoors) | Sep 13–27 (sowing) |
| Arugula | – | Mar 25–Apr 22 (sow outdoors) | Sep 13–Oct 11 (sowing) |
| Mustard greens | – | Mar 25–Apr 15 (sow outdoors) | Sep 13–27 (sowing) |
| Swiss chard | Mar 11–25 | Apr 8–29 (transplant) Apr 8–May 6 (sow outdoors) | Aug 30–Sep 13 (sowing) |
| Beet | – | Mar 25–Apr 22 (sow outdoors) | Aug 30–Sep 13 (sowing) |
| Carrot | – | Apr 1–29 (sow outdoors) | Aug 16–30 (sowing) |
| Radish | – | Mar 18–Apr 29 (sow outdoors) | Sep 27–Oct 11 (sowing) |
| Turnip | – | Mar 25–Apr 15 (sow outdoors) | Aug 30–Sep 13 (sowing) |
| Parsnip | – | Apr 1–22 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Feb 25–Mar 25 (sow outdoors) | Aug 16–30 (sowing) |
| Onion (bulbing) | Jan 28–Feb 11 | Mar 11–25 (transplant) | – |
| Green onion / scallion | – | Mar 11–Apr 8 (sow outdoors) | Aug 30–Sep 13 (sowing) |
| Leek | Jan 28–Feb 11 | Mar 25–Apr 8 (transplant) | – |
| Garlic | – | – | Sep 27–Oct 25 (sowing) |
| Shallot | – | Mar 11–25 (transplant) | Sep 27–Oct 25 (sowing) |
| Potato | – | Mar 25–Apr 8 (transplant) | Jul 19–Aug 2 (transplant) |
| Sweet potato | – | May 13–27 (transplant) | – |
| Sweet corn | – | Apr 29–May 13 (sow outdoors) | – |
| Bean, bush (snap) | – | Apr 29–May 13 (sow outdoors) | – |
| Bean, pole | – | Apr 29–May 13 (sow outdoors) | – |
| Lima bean | – | May 6–20 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 13–Jun 3 (sow outdoors) | – |
| Cucumber | Mar 25–Apr 1 | Apr 29–May 13 (transplant) Apr 29–May 13 (sow outdoors) | – |
| Summer squash / zucchini | Mar 25–Apr 1 | Apr 29–May 13 (transplant) Apr 29–May 13 (sow outdoors) | – |
| Winter squash | Mar 25–Apr 1 | Apr 29–May 13 (transplant) Apr 29–May 13 (sow outdoors) | – |
| Pumpkin | – | Apr 29–May 13 (sow outdoors) | – |
| Watermelon | Mar 25–Apr 1 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 25–Apr 1 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Okra | Mar 11–25 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Celery | Jan 28–Feb 11 | Apr 29–May 6 (transplant) | – |
| Basil | Mar 11–25 | Apr 29–May 13 (transplant) Apr 29–May 13 (sow outdoors) | – |
| Cilantro | – | Apr 8–May 6 (sow outdoors) | Sep 13–27 (sowing) |
| Parsley | Feb 11–25 | Apr 8–22 (transplant) Apr 1–22 (sow outdoors) | – |
| Dill | – | Apr 22–May 6 (sow outdoors) | Sep 13–27 (sowing) |
| Sunflower | – | Apr 22–May 6 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 25–Apr 8 (transplant) | – |
| Rhubarb (crowns) | – | Mar 25–Apr 8 (transplant) | – |
| Strawberry (plants) | – | Mar 25–Apr 8 (transplant) | Aug 30–Sep 27 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Where these numbers come from
Station: Mt Laguna #3, CA (NOAA GHCN-Daily ID USC00045968), elevation 5,920 ft, 3.1 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Cuyamaca, CA | 11 mi | Apr 19 | Oct 27 |
| Julian Cdf, CA | 16 mi | Mar 27 | Dec 1 |
| Campo, CA | 16 mi | Apr 30 | Oct 26 |
The average last-frost dates of these stations span 34 days, a rough guide to local variation. See data sources & methods.
Frost questions for 91948
When is the last frost in 91948?
The average (50% chance) last spring freeze of 32°F for ZIP 91948 is April 22. For a more cautious planting date, use May 21, when only 1 year in 10 still sees a later freeze.
When is the first frost in 91948?
The average first fall freeze is November 8. In 1 year in 10 it comes by October 10.
What hardiness zone is 91948?
ZIP 91948 is in USDA zone 8a (10 to 15°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 91948 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
91962 Pine Valley 91931 91916 Descanso 91906 Campo 91901 Alpine 91905 Boulevard 91963 Potrero 92036 Julian
Other ZIP codes in San Diego County
91901 91902 91905 91906 91910 91911 91913 91914 91915 91916 91917 91931 91932 91934 91935 91941 91942 91945 91950 91962 91963 91977 91978 91980 All San Diego County frost dates · California frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
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Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.