Catheys Valley, CA planting calendar

USDA hardiness zone 9b · nearest station Merced (14.7 km) · NOAA 1991–2020 normals

USDA zone
9b25 to 30 °F
Last frost
Mar 3avg, 32°F
First frost
Nov 24avg, 32°F
Growing season
263days

Catheys Valley, California is in USDA plant hardiness zone 9b. Its average last spring frost is around March 3 and the first fall frost around November 24, giving a growing season of about 263 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.

Catheys Valley planting calendar

Each crop's windows are counted from Catheys 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 Catheys 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 6 – Jan 20 Mar 10 – Mar 17 May 9 – May 29
Pepper Very tender Jan 1 – Jan 6 Mar 17 – Mar 24 May 16 – Jun 15
Cucumber Tender Feb 3 – Feb 10 Mar 10 – Mar 17 Apr 29 – May 19
Summer squash / zucchini Tender Mar 10 – Mar 17 Apr 24 – May 9
Bush bean Tender Mar 10 – Mar 17 Apr 29 – May 9 Sep 25 – Oct 5
Sweet corn Tender Mar 3 – Mar 17 May 2 – Jun 1
Basil Very tender Jan 20 – Feb 3 Mar 10 – Mar 17 Apr 9 – Apr 24
Lettuce Half-hardy Jan 20 – Feb 3 Feb 3 – Feb 17 Mar 20 – Apr 4 Sep 11 – Sep 26
Pea Hardy Jan 20 – Feb 3 Mar 16 – Mar 31 Sep 1 – Sep 16
Spinach Hardy Jan 20 – Feb 3 Mar 1 – Mar 11 Sep 21 – Oct 1
Carrot Half-hardy Feb 10 – Feb 17 Apr 11 – May 1 Aug 22 – Sep 11
Broccoli Half-hardy Jan 6 – Jan 20 Feb 3 – Feb 17 Mar 30 – Apr 19 Aug 27 – Sep 16

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 USC00045532. 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 Apr 7 May 1 Nov 8 Nov 24 213
32°F (freeze) Mar 3 Apr 10 Nov 24 Dec 14 263
28°F Feb 2 Mar 11 Dec 11 Jan 14 318
24°F Jan 9 Feb 11 Dec 24 Jan 24 358

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 Catheys Valley (°F·days, NOAA 1991–2020).
Model °F·days Used for
Base 50°F (warm-season) 4,678 standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season) 7,917 cool-season crops (brassicas, greens)

Hardiness zone 9b

Catheys Valley sits in USDA plant hardiness zone 9b on the 2023 map — meaning its average annual extreme minimum winter temperature is about 25 to 30 °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 9b, or see all USDA hardiness zones.

Frequently asked questions

What USDA hardiness zone is Catheys Valley?
Catheys Valley, California is in USDA plant hardiness zone 9b on the 2023 map (average annual extreme minimum temperature 25 to 30 °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 Catheys Valley?
The average (median) last spring frost at 32°F is around March 3, 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 10, so wait until then before setting out frost-tender plants if you want to be safe.
When is the first fall frost in Catheys Valley?
The average first fall frost at 32°F is around November 24. That leaves a growing season of about 263 days between the average last spring and first fall frosts.
When should I start tomatoes in Catheys Valley?
Start tomato seeds indoors about Jan 6 – Jan 20 and transplant them outside about Mar 10 – Mar 17, once the danger of frost has passed. Estimated first harvest is around May 9 – May 29.
How long is the growing season in Catheys Valley?
About 263 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~March 3) and the average first fall frost (~November 24). 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 USC00045532 (Merced, 14.7 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.