Frost Dates & Planting Calendar for Alpine, CA
Plan your garden around Alpine, CA's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.
Last Spring Frost
February 12
Safe Mar 20
Typical Feb 12
Risky Dec 29
First Fall Frost
December 24
Safe Dec 2
Typical Dec 24
Risky Feb 3
Growing Season
317 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 9b
Subtropical to frost-free — heat, not cold, is the main limit on what you can grow.
Data: NOAA station ALPINE, CA US, 1 km away.
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days until the typical last spring frost
Monthly Temperatures
Avg. high
Avg. temp
Avg. low
Planting Calendar
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Tomato | Dec 18 – Jan 1 | — | Feb 19 – Feb 26 | — | 60–85 days | Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed. |
| Pepper | Dec 4 – Dec 18 | — | Feb 19 – Mar 5 | — | 60–90 days | Slow to germinate; start indoors 8-10 weeks before last frost. Transplant only once nights stay above 55F, 1-3 weeks after last frost. |
| Eggplant | Dec 4 – Dec 18 | — | Feb 26 – Mar 5 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Jan 15 – Jan 22 | Feb 19 – Feb 26 | Feb 19 – Feb 26 | — | 50–65 days | Can be started indoors 3-4 weeks before transplanting, or direct-sown 1-2 weeks after last frost once soil is warm. |
| Zucchini | Jan 22 – Jan 29 | Feb 19 – Mar 5 | Feb 19 – Feb 26 | — | 45–55 days | Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start. |
| Winter Squash | Jan 15 – Jan 22 | Feb 19 – Mar 5 | Feb 19 – Feb 26 | — | 80–110 days | Long season; direct sow after soil warms, or start indoors 3-4 weeks before last frost in short-season climates. |
| Pumpkin | — | Feb 19 – Mar 5 | — | — | 90–120 days | Direct sow 1-3 weeks after last frost; back-time from your first fall frost so the 90-120 day maturity window lands before it. |
| Watermelon | Jan 15 – Jan 22 | — | Feb 26 – Mar 5 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Jan 15 – Jan 22 | — | Feb 26 – Mar 5 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Feb 12 – Feb 26 | — | — | 60–100 days | Direct sow at last frost to 2 weeks after, once soil reaches 60F; does not transplant well. Succession sow every 2 weeks. |
| Green Bean | — | Feb 12 – Feb 26 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Jan 1 – Jan 15 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Jan 15 – Jan 29 | — | Oct 29 – Nov 12 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Jan 1 – Jan 15 | — | Oct 29 – Nov 12 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Jan 15 – Jan 29 | — | Oct 15 – Oct 29 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Jan 15 – Jan 29 | — | Nov 12 – Nov 19 | 30–40 days | Fast-growing, cold-tolerant green; direct sow 2-4 weeks before last frost, succession sow every 2-3 weeks. |
| Swiss Chard | — | Jan 22 – Feb 5 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Dec 25 – Jan 8 | — | Jan 22 – Jan 29 | Oct 22 – Oct 29 | 55–80 days | Start indoors 5-7 weeks before last frost; transplant out 2-3 weeks before last frost (hardens off to light frost). |
| Cauliflower | Dec 25 – Jan 8 | — | Jan 29 – Feb 5 | Oct 15 – Oct 22 | 55–85 days | Fussier than broccoli about temperature swings; start indoors 5-7 weeks before last frost, transplant 1-2 weeks before last frost. |
| Cabbage | Dec 25 – Jan 8 | — | Jan 15 – Jan 29 | Oct 15 – Oct 29 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Dec 25 – Jan 8 | — | Jan 22 – Feb 5 | — | 90–110 days | Long-season crop best timed to mature after a light fall frost for sweetest flavor; start indoors 5-7 weeks before last frost. |
| Carrot | — | Jan 15 – Jan 29 | — | Oct 1 – Oct 15 | 60–80 days | Direct sow only (does not transplant); sow 2-4 weeks before last frost, as soon as soil can be worked. |
| Beet | — | Jan 15 – Jan 29 | — | Oct 15 – Oct 29 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Jan 8 – Jan 22 | — | Nov 12 – Nov 26 | 22–30 days | Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked. |
| Turnip | — | Jan 15 – Jan 29 | — | Oct 15 – Oct 29 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Dec 4 – Dec 18 | — | Jan 15 – Jan 29 | — | 90–120 days | Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings. |
| Garlic | — | — | — | Nov 26 – Dec 10 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Jan 15 – Jan 29 | — | — | 70–120 days | Plant seed potatoes 2-4 weeks before last frost, as soon as soil can be worked and is above 45F; light frost on emerging foliage is usually tolerated. |
| Sweet Potato | — | — | Feb 26 – Mar 12 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Jan 15 – Jan 29 | — | 730–1095 days | Perennial; plant crowns 2-4 weeks before last frost as soon as soil can be worked. Takes 2-3 years to full production. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Basil | Jan 1 – Jan 8 | — | Feb 19 – Feb 26 | — | 50–70 days | Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm. |
| Cilantro | — | Jan 22 – Feb 5 | — | Oct 29 – Nov 12 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Dec 18 – Jan 1 | — | Jan 29 – Feb 5 | — | 70–90 days | Slow to germinate; start indoors 6-8 weeks before last frost, transplant 1-2 weeks before last frost (biennial, cold-tolerant). |
| Dill | — | Jan 22 – Feb 5 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Dec 18 – Jan 1 | — | Feb 12 – Feb 19 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Dec 18 – Jan 1 | — | Feb 12 – Feb 19 | — | 85–95 days | Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Sunflower | — | Feb 19 – Mar 5 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Jan 15 – Jan 22 | Feb 19 – Mar 5 | Feb 19 – Feb 26 | — | 60–70 days | Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms. |
| Marigold | Jan 1 – Jan 15 | — | Feb 19 – Feb 26 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Jan 15 – Jan 22 | Feb 19 – Mar 5 | Feb 19 – Feb 26 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Feb 19 – Mar 5 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Feb 19 – Mar 5 | — | 90–120 days | Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive. |
Date ranges are estimates based on university extension guidelines and this city's NOAA frost normals — not a guarantee. Scroll to see all columns on narrow screens.
Frequently Asked Questions
When is the last frost in Alpine, CA?
Based on 1991–2020 NOAA climate normals for the ALPINE, CA US station, the last spring frost in Alpine typically falls around February 12. A cautious gardener might wait until March 20 (only a 10% chance of a later frost), while December 29 marks an earlier, higher-risk planting date.
When is the first frost in Alpine, CA in fall?
The first fall frost in Alpine typically arrives around December 24. To stay safe, assume frost could start as early as December 2; in milder years it can hold off until February 3.
How long is the growing season in Alpine, CA?
Alpine's average frost-free growing season is about 317 days, running from the typical last spring frost (February 12) to the typical first fall frost (December 24).
What USDA hardiness zone is Alpine, CA in?
Alpine, CA is in USDA plant hardiness zone 9b, per the USDA's 2023 Plant Hardiness Zone Map. Subtropical to frost-free — heat, not cold, is the main limit on what you can grow.