Piñon Hills, CA 93553 planting calendar
- USDA zone
- 8b15 to 20 °F
- Last frost
- Mar 13avg, 32°F
- First frost
- Dec 1avg, 32°F
- Growing season
- 258days
Piñon Hills, California is in USDA plant hardiness zone 8b. Its average last spring frost is around March 13 and the first fall frost around December 1, giving a growing season of about 258 days (NOAA 1991–2020 normals, 32°F, median). Start tender crops like tomatoes and peppers indoors weeks before the last frost and set them out afterward; sow hardy crops such as peas, spinach, and lettuce before it. The planner below turns those frost dates into a printable per-crop planting calendar.
Piñon Hills planting calendar
Each crop's windows are counted from Piñon Hills's average frost dates. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees.
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting |
|---|---|---|---|---|---|
| Tomato | Tender | Jan 16 – Jan 30 | Mar 20 – Mar 27 | May 19 – Jun 8 | — |
| Pepper | Very tender | Jan 2 – Jan 16 | Mar 27 – Apr 3 | May 26 – Jun 25 | — |
| Cucumber | Tender | Feb 13 – Feb 20 | Mar 20 – Mar 27 | May 9 – May 29 | — |
| Summer squash / zucchini | Tender | — | Mar 20 – Mar 27 | May 4 – May 19 | — |
| Bush bean | Tender | — | Mar 20 – Mar 27 | May 9 – May 19 | Oct 2 – Oct 12 |
| Sweet corn | Tender | — | Mar 13 – Mar 27 | May 12 – Jun 11 | — |
| Basil | Very tender | Jan 30 – Feb 13 | Mar 20 – Mar 27 | Apr 19 – May 4 | — |
| Lettuce | Half-hardy | Jan 30 – Feb 13 | Feb 13 – Feb 27 | Mar 30 – Apr 14 | Sep 18 – Oct 3 |
| Pea | Hardy | — | Jan 30 – Feb 13 | Mar 26 – Apr 10 | Sep 8 – Sep 23 |
| Spinach | Hardy | — | Jan 30 – Feb 13 | Mar 11 – Mar 21 | Sep 28 – Oct 8 |
| Carrot | Half-hardy | — | Feb 20 – Feb 27 | Apr 21 – May 11 | Aug 29 – Sep 18 |
| Broccoli | Half-hardy | Jan 16 – Jan 30 | Feb 13 – Feb 27 | Apr 9 – Apr 29 | Sep 3 – Sep 23 |
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Frost & freeze dates
From NOAA's 1991–2020 Climate Normals at station USC00046773. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 (p10 for spring, p90 for fall) — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | Apr 14 | May 9 | Nov 16 | Dec 3 | 216 |
| 32°F (freeze) | Mar 13 | Apr 17 | Dec 1 | Dec 18 | 258 |
| 28°F | Feb 9 | Mar 18 | Dec 12 | Jan 16 | 312 |
| 24°F | Jan 10 | Feb 18 | Dec 30 | Feb 5 | 363 |
32°F is the standard "freeze" line that damages tender crops; lighter 36°F frost can nip the most cold-sensitive plants, while hardy crops shrug off light frost down toward 28°F. Use the threshold that matches what you are protecting.
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. Warm-season crops need a long, warm GDD total; a short, cool GDD total favors greens and brassicas.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 5,595 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 8,910 | cool-season crops (brassicas, greens) |
Hardiness zone 8b
Piñon Hills sits in USDA plant hardiness zone 8b on the 2023 map — meaning its average annual extreme minimum winter temperature is about 15 to 20 °F. That number tells you which perennials, shrubs, and trees reliably survive an average winter here; it does not set your planting dates, which come from the frost calendar above.
Explore more places in zone 8b, or see all USDA hardiness zones.
Frequently asked questions
- What USDA hardiness zone is Piñon Hills?
- Piñon Hills, California is in USDA plant hardiness zone 8b on the 2023 map (average annual extreme minimum temperature 15 to 20 °F) — from the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. See the methodology page for sources.
- When is the last frost in Piñon Hills?
- The average (median) last spring frost at 32°F is around March 13, from NOAA's 1991–2020 climate normals at the nearest reporting station. Roughly one year in ten the last frost is as late as April 17, so wait until then before setting out frost-tender plants if you want to be safe.
- When is the first fall frost in Piñon Hills?
- The average first fall frost at 32°F is around December 1. That leaves a growing season of about 258 days between the average last spring and first fall frosts.
- When should I start tomatoes in Piñon Hills?
- Start tomato seeds indoors about Jan 16 – Jan 30 and transplant them outside about Mar 20 – Mar 27, once the danger of frost has passed. Estimated first harvest is around May 19 – Jun 8.
- How long is the growing season in Piñon Hills?
- About 258 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~March 13) and the average first fall frost (~December 1). Cold-hardy crops extend usable time at both ends; frost-tender crops fit inside it.
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020 for station USC00046773 (Pearblossom, 6.4 km away). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.