Frost Dates & Planting Calendar for Half Moon Bay, CA
Plan your garden around Half Moon Bay, 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 6
Safe Mar 25
Typical Feb 6
Risky Dec 17
First Fall Frost
December 17
Safe Nov 25
Typical Dec 17
Risky Feb 13
Growing Season
328 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 10a
Subtropical to frost-free — heat, not cold, is the main limit on what you can grow.
Data: NOAA station HALF MOON BAY, CA US, 1.6 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 12 – Dec 26 | — | Feb 13 – Feb 20 | — | 60–85 days | Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed. |
| Pepper | Nov 28 – Dec 12 | — | Feb 13 – Feb 27 | — | 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 | Nov 28 – Dec 12 | — | Feb 20 – Feb 27 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Jan 9 – Jan 16 | Feb 13 – Feb 20 | Feb 13 – Feb 20 | — | 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 16 – Jan 23 | Feb 13 – Feb 27 | Feb 13 – Feb 20 | — | 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 9 – Jan 16 | Feb 13 – Feb 27 | Feb 13 – Feb 20 | — | 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 13 – Feb 27 | — | — | 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 9 – Jan 16 | — | Feb 20 – Feb 27 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Jan 9 – Jan 16 | — | Feb 20 – Feb 27 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Feb 6 – Feb 20 | — | — | 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 6 – Feb 20 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Dec 26 – Jan 9 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Jan 9 – Jan 23 | — | Oct 22 – Nov 5 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Dec 26 – Jan 9 | — | Oct 22 – Nov 5 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Jan 9 – Jan 23 | — | Oct 8 – Oct 22 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Jan 9 – Jan 23 | — | Nov 5 – Nov 12 | 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 16 – Jan 30 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Dec 19 – Jan 2 | — | Jan 16 – Jan 23 | Oct 15 – Oct 22 | 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 19 – Jan 2 | — | Jan 23 – Jan 30 | Oct 8 – Oct 15 | 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 19 – Jan 2 | — | Jan 9 – Jan 23 | Oct 8 – Oct 22 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Dec 19 – Jan 2 | — | Jan 16 – Jan 30 | — | 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 9 – Jan 23 | — | Sep 24 – Oct 8 | 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 9 – Jan 23 | — | Oct 8 – Oct 22 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Jan 2 – Jan 16 | — | Nov 5 – Nov 19 | 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 9 – Jan 23 | — | Oct 8 – Oct 22 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Nov 28 – Dec 12 | — | Jan 9 – Jan 23 | — | 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 19 – Dec 3 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Jan 9 – Jan 23 | — | — | 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 20 – Mar 6 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Jan 9 – Jan 23 | — | 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 | Dec 26 – Jan 2 | — | Feb 13 – Feb 20 | — | 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 16 – Jan 30 | — | Oct 22 – Nov 5 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Dec 12 – Dec 26 | — | Jan 23 – Jan 30 | — | 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 16 – Jan 30 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Dec 12 – Dec 26 | — | Feb 6 – Feb 13 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Dec 12 – Dec 26 | — | Feb 6 – Feb 13 | — | 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 13 – Feb 27 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Jan 9 – Jan 16 | Feb 13 – Feb 27 | Feb 13 – Feb 20 | — | 60–70 days | Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms. |
| Marigold | Dec 26 – Jan 9 | — | Feb 13 – Feb 20 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Jan 9 – Jan 16 | Feb 13 – Feb 27 | Feb 13 – Feb 20 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Feb 13 – Feb 27 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Feb 13 – Feb 27 | — | 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 Half Moon Bay, CA?
Based on 1991–2020 NOAA climate normals for the HALF MOON BAY, CA US station, the last spring frost in Half Moon Bay typically falls around February 6. A cautious gardener might wait until March 25 (only a 10% chance of a later frost), while December 17 marks an earlier, higher-risk planting date.
When is the first frost in Half Moon Bay, CA in fall?
The first fall frost in Half Moon Bay typically arrives around December 17. To stay safe, assume frost could start as early as November 25; in milder years it can hold off until February 13.
How long is the growing season in Half Moon Bay, CA?
Half Moon Bay's average frost-free growing season is about 328 days, running from the typical last spring frost (February 6) to the typical first fall frost (December 17).
What USDA hardiness zone is Half Moon Bay, CA in?
Half Moon Bay, CA is in USDA plant hardiness zone 10a, 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.