Searles Valley, CA planting calendar

USDA hardiness zone 9a · nearest station Trona (10.2 km) · NOAA 1991–2020 normals

USDA zone
9a20 to 25 °F
Last frost
Feb 15avg, 32°F
First frost
Nov 28avg, 32°F
Growing season
285days

Searles Valley, California is in USDA plant hardiness zone 9a. Its average last spring frost is around February 15 and the first fall frost around November 28, giving a growing season of about 285 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.

Searles Valley planting calendar

Each crop's windows are counted from Searles Valley'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
Planting windows for Searles Valley. Dates are planning ranges from U.S. Cooperative Extension guides.
Crop Frost tolerance Start indoors Plant out First harvest Fall planting
Tomato Tender Jan 1 – Jan 4 Feb 22 – Mar 1 Apr 23 – May 13
Pepper Very tender Jan 1 Mar 1 – Mar 8 Apr 30 – May 30
Cucumber Tender Jan 18 – Jan 25 Feb 22 – Mar 1 Apr 13 – May 3
Summer squash / zucchini Tender Feb 22 – Mar 1 Apr 8 – Apr 23
Bush bean Tender Feb 22 – Mar 1 Apr 13 – Apr 23 Sep 29 – Oct 9
Sweet corn Tender Feb 15 – Mar 1 Apr 16 – May 16
Basil Very tender Jan 4 – Jan 18 Feb 22 – Mar 1 Mar 24 – Apr 8
Lettuce Half-hardy Jan 4 – Jan 18 Jan 18 – Feb 1 Mar 4 – Mar 19 Sep 15 – Sep 30
Pea Hardy Jan 4 – Jan 18 Feb 28 – Mar 15 Sep 5 – Sep 20
Spinach Hardy Jan 4 – Jan 18 Feb 13 – Feb 23 Sep 25 – Oct 5
Carrot Half-hardy Jan 25 – Feb 1 Mar 26 – Apr 15 Aug 26 – Sep 15
Broccoli Half-hardy Jan 1 – Jan 4 Jan 18 – Feb 1 Mar 14 – Apr 3 Aug 31 – Sep 20

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 USC00049035. 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.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020).
Threshold Last spring — avg Last spring — 90%-safe First fall — avg First fall — 90%-safe Season (days)
36°F Mar 4 Apr 4 Nov 17 Dec 2 257
32°F (freeze) Feb 15 Mar 4 Nov 28 Dec 16 285
28°F Jan 23 Feb 19 Dec 10 Jan 2 321
24°F Jan 7 Feb 7 Dec 23 Jan 23 352

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.

Annual growing degree days for Searles Valley (°F·days, NOAA 1991–2020).
Model °F·days Used for
Base 50°F (warm-season) 7,073 standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season) 10,419 cool-season crops (brassicas, greens)

Hardiness zone 9a

Searles Valley sits in USDA plant hardiness zone 9a on the 2023 map — meaning its average annual extreme minimum winter temperature is about 20 to 25 °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 9a, or see all USDA hardiness zones.

Frequently asked questions

What USDA hardiness zone is Searles Valley?
Searles Valley, California is in USDA plant hardiness zone 9a on the 2023 map (average annual extreme minimum temperature 20 to 25 °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 Searles Valley?
The average (median) last spring frost at 32°F is around February 15, from NOAA's 1991–2020 climate normals at the nearest reporting station. Roughly one year in ten the last frost is as late as March 4, so wait until then before setting out frost-tender plants if you want to be safe.
When is the first fall frost in Searles Valley?
The average first fall frost at 32°F is around November 28. That leaves a growing season of about 285 days between the average last spring and first fall frosts.
When should I start tomatoes in Searles Valley?
Start tomato seeds indoors about Jan 1 – Jan 4 and transplant them outside about Feb 22 – Mar 1, once the danger of frost has passed. Estimated first harvest is around Apr 23 – May 13.
How long is the growing season in Searles Valley?
About 285 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~February 15) and the average first fall frost (~November 28). 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 USC00049035 (Trona, 10.2 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.