Fall in zone 9aPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 91905 (Boulevard, 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, Campo Asos, CA (10 miles away).
- Average last spring frostApr 2950% chance of a 32°F freeze after this date
- Average first fall frostNov 150% chance of a 32°F freeze by this date
- Growing season (frost-free)184 daysmedian, 32°F threshold
- USDA hardiness zone9a20 to 25°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
No soil station with a fresh reading within 62 miles.
4-inch depth
No soil station with a fresh reading within 62 miles.
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 91905 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
No soil reading near this ZIP. Typical extension timing for your region: spring February to March; fall 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 14 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 1: 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) | Apr 7 |
| 50% (the "average" last frost) | Apr 29 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 1 |
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 5 |
| 50% (the "average" first frost) | Nov 1 |
| 90% (late: most years have frozen by now) | Nov 23 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 31 | Oct 8 |
| 32°F (freeze) | Apr 29 | Nov 1 |
| 28°F (hard freeze) | Mar 31 | Nov 27 |
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 91905
Dates count from your average last spring frost (Apr 29) and first fall frost (Nov 1). 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 | Mar 4–18 | May 6–20 (transplant) | – |
| Pepper (sweet and hot) | Feb 18–Mar 4 | May 13–27 (transplant) | – |
| Eggplant | Feb 18–Mar 4 | May 13–27 (transplant) | – |
| Tomatillo | Mar 4–18 | May 6–20 (transplant) | – |
| Lettuce | Mar 4–18 | Apr 8–29 (transplant) Apr 1–May 13 (sow outdoors) | Sep 6–27 (transplant) Aug 23–Sep 20 (sowing) |
| Spinach | – | Mar 18–Apr 8 (sow outdoors) | Sep 6–27 (sowing) |
| Kale | Mar 4–18 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | Aug 9–Sep 6 (transplant) Jul 26–Aug 23 (sowing) |
| Collards | Mar 4–18 | Apr 1–29 (transplant) Apr 1–29 (sow outdoors) | Aug 9–Sep 6 (transplant) Jul 26–Aug 23 (sowing) |
| Broccoli | Feb 18–Mar 4 | Apr 1–15 (transplant) | Jul 26–Aug 23 (transplant) |
| Cabbage | Feb 18–Mar 4 | Apr 1–15 (transplant) | Jul 26–Aug 23 (transplant) |
| Cauliflower | Feb 18–Mar 4 | Apr 15–29 (transplant) | Jul 26–Aug 23 (transplant) |
| Brussels sprouts | Feb 4–18 | Apr 1–15 (transplant) | Jul 12–Aug 2 (transplant) |
| Kohlrabi | Mar 4–18 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Bok choy / Asian greens | – | Apr 1–15 (sow outdoors) | Sep 6–20 (sowing) |
| Arugula | – | Apr 1–29 (sow outdoors) | Sep 6–Oct 4 (sowing) |
| Mustard greens | – | Apr 1–22 (sow outdoors) | Sep 6–20 (sowing) |
| Swiss chard | Mar 18–Apr 1 | Apr 15–May 6 (transplant) Apr 15–May 13 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Beet | – | Apr 1–29 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Carrot | – | Apr 8–May 6 (sow outdoors) | Aug 9–23 (sowing) |
| Radish | – | Mar 25–May 6 (sow outdoors) | Sep 20–Oct 4 (sowing) |
| Turnip | – | Apr 1–22 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Parsnip | – | Apr 8–29 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 4–Apr 1 (sow outdoors) | Aug 9–23 (sowing) |
| Onion (bulbing) | Feb 4–18 | Mar 18–Apr 1 (transplant) | – |
| Green onion / scallion | – | Mar 18–Apr 15 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Leek | Feb 4–18 | Apr 1–15 (transplant) | – |
| Garlic | – | – | Sep 20–Oct 18 (sowing) |
| Shallot | – | Mar 18–Apr 1 (transplant) | Sep 20–Oct 18 (sowing) |
| Potato | – | Apr 1–15 (transplant) | Jul 12–26 (transplant) |
| Sweet potato | – | May 20–Jun 3 (transplant) | – |
| Sweet corn | – | May 6–20 (sow outdoors) | – |
| Bean, bush (snap) | – | May 6–20 (sow outdoors) | – |
| Bean, pole | – | May 6–20 (sow outdoors) | – |
| Lima bean | – | May 13–27 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 20–Jun 10 (sow outdoors) | – |
| Cucumber | Apr 1–8 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Summer squash / zucchini | Apr 1–8 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Winter squash | Apr 1–8 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Pumpkin | – | May 6–20 (sow outdoors) | – |
| Watermelon | Apr 1–8 | May 13–27 (transplant) May 13–27 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 1–8 | May 13–27 (transplant) May 13–27 (sow outdoors) | – |
| Okra | Mar 18–Apr 1 | May 13–27 (transplant) May 13–27 (sow outdoors) | – |
| Celery | Feb 4–18 | May 6–13 (transplant) | – |
| Basil | Mar 18–Apr 1 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Cilantro | – | Apr 15–May 13 (sow outdoors) | Sep 6–20 (sowing) |
| Parsley | Feb 18–Mar 4 | Apr 15–29 (transplant) Apr 8–29 (sow outdoors) | – |
| Dill | – | Apr 29–May 13 (sow outdoors) | Sep 6–20 (sowing) |
| Sunflower | – | Apr 29–May 13 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 1–15 (transplant) | – |
| Rhubarb (crowns) | – | Apr 1–15 (transplant) | – |
| Strawberry (plants) | – | Apr 1–15 (transplant) | Aug 23–Sep 20 (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: Campo Asos, CA (NOAA GHCN-Daily ID USW00003164), elevation 2,641 ft, 10.0 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Campo, CA | 10 mi | Apr 30 | Oct 26 |
| Mt Laguna #3, CA | 15 mi | Apr 22 | Nov 8 |
| Cuyamaca, CA | 27 mi | Apr 19 | Oct 27 |
The average last-frost dates of these stations span 11 days, a rough guide to local variation. See data sources & methods.
Frost questions for 91905
When is the last frost in 91905?
The average (50% chance) last spring freeze of 32°F for ZIP 91905 is April 29. For a more cautious planting date, use June 1, when only 1 year in 10 still sees a later freeze.
When is the first frost in 91905?
The average first fall freeze is November 1. In 1 year in 10 it comes by October 5.
What hardiness zone is 91905?
ZIP 91905 is in USDA zone 9a (20 to 25°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 91905 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
91934 Jacumba 91906 Campo 91948 Mount Laguna 91963 Potrero 91962 Pine Valley 91931 91980 92259 Ocotillo
Other ZIP codes in San Diego County
91901 91902 91906 91910 91911 91913 91914 91915 91916 91917 91931 91932 91934 91935 91941 91942 91945 91948 91950 91962 91963 91977 91978 91980 All San Diego County frost dates · California frost dates
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- 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.