San Jose, CA 95140 planting calendar
- USDA zone
- 9b25 to 30 °F
- Last frost
- May 3avg, 32°F
- First frost
- Nov 18avg, 32°F
- Growing season
- 197days
San Jose, California is in USDA plant hardiness zone 9b. Its average last spring frost is around May 3 and the first fall frost around November 18, giving a growing season of about 197 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.
San Jose planting calendar
Each crop's windows are counted from San Jose'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 | Mar 8 – Mar 22 | May 10 – May 17 | Jul 9 – Jul 29 | — |
| Pepper | Very tender | Feb 22 – Mar 8 | May 17 – May 24 | Jul 16 – Aug 15 | — |
| Cucumber | Tender | Apr 5 – Apr 12 | May 10 – May 17 | Jun 29 – Jul 19 | — |
| Summer squash / zucchini | Tender | — | May 10 – May 17 | Jun 24 – Jul 9 | — |
| Bush bean | Tender | — | May 10 – May 17 | Jun 29 – Jul 9 | Sep 19 – Sep 29 |
| Sweet corn | Tender | — | May 3 – May 17 | Jul 2 – Aug 1 | — |
| Basil | Very tender | Mar 22 – Apr 5 | May 10 – May 17 | Jun 9 – Jun 24 | — |
| Lettuce | Half-hardy | Mar 22 – Apr 5 | Apr 5 – Apr 19 | May 20 – Jun 4 | Sep 5 – Sep 20 |
| Pea | Hardy | — | Mar 22 – Apr 5 | May 16 – May 31 | Aug 26 – Sep 10 |
| Spinach | Hardy | — | Mar 22 – Apr 5 | May 1 – May 11 | Sep 15 – Sep 25 |
| Carrot | Half-hardy | — | Apr 12 – Apr 19 | Jun 11 – Jul 1 | Aug 16 – Sep 5 |
| Broccoli | Half-hardy | Mar 8 – Mar 22 | Apr 5 – Apr 19 | May 30 – Jun 19 | Aug 21 – Sep 10 |
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 USC00045933. 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 | May 27 | Jun 18 | Oct 29 | Nov 23 | 155 |
| 32°F (freeze) | May 3 | Jun 5 | Nov 18 | Dec 12 | 197 |
| 28°F | Apr 10 | May 6 | Dec 7 | Jan 18 | 241 |
| 24°F | Mar 1 | Apr 11 | Jan 1 | Mar 2 | 305 |
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) | 3,173 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 5,803 | cool-season crops (brassicas, greens) |
Hardiness zone 9b
San Jose 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 San Jose?
- San Jose, 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 San Jose?
- The average (median) last spring frost at 32°F is around May 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 June 5, so wait until then before setting out frost-tender plants if you want to be safe.
- When is the first fall frost in San Jose?
- The average first fall frost at 32°F is around November 18. That leaves a growing season of about 197 days between the average last spring and first fall frosts.
- When should I start tomatoes in San Jose?
- Start tomato seeds indoors about Mar 8 – Mar 22 and transplant them outside about May 10 – May 17, once the danger of frost has passed. Estimated first harvest is around Jul 9 – Jul 29.
- How long is the growing season in San Jose?
- About 197 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~May 3) and the average first fall frost (~November 18). 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 USC00045933 (Mt Hamilton, 0.9 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.