Frost Dates & Planting Calendar for Santa Rosa, CA
Plan your garden around Santa Rosa, 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 25
Safe Mar 29
Typical Feb 25
Risky Jan 21
First Fall Frost
December 1
Safe Nov 10
Typical Dec 1
Risky Dec 24
Growing Season
279 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 SANTA ROSA, CA US, 1.7 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 31 – Jan 14 | — | Mar 4 – Mar 11 | — | 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 17 – Dec 31 | — | Mar 4 – Mar 18 | — | 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 17 – Dec 31 | — | Mar 11 – Mar 18 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Jan 28 – Feb 4 | Mar 4 – Mar 11 | Mar 4 – Mar 11 | — | 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 | Feb 4 – Feb 11 | Mar 4 – Mar 18 | Mar 4 – Mar 11 | — | 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 28 – Feb 4 | Mar 4 – Mar 18 | Mar 4 – Mar 11 | — | 80–110 days | Long season; direct sow after soil warms, or start indoors 3-4 weeks before last frost in short-season climates. |
| Pumpkin | — | Mar 4 – Mar 18 | — | — | 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 28 – Feb 4 | — | Mar 11 – Mar 18 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Jan 28 – Feb 4 | — | Mar 11 – Mar 18 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Feb 25 – Mar 11 | — | — | 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 25 – Mar 11 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Jan 14 – Jan 28 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Jan 28 – Feb 11 | — | Oct 6 – Oct 20 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Jan 14 – Jan 28 | — | Oct 6 – Oct 20 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Jan 28 – Feb 11 | — | Sep 22 – Oct 6 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Jan 28 – Feb 11 | — | Oct 20 – Oct 27 | 30–40 days | Fast-growing, cold-tolerant green; direct sow 2-4 weeks before last frost, succession sow every 2-3 weeks. |
| Swiss Chard | — | Feb 4 – Feb 18 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Jan 7 – Jan 21 | — | Feb 4 – Feb 11 | Sep 29 – Oct 6 | 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 | Jan 7 – Jan 21 | — | Feb 11 – Feb 18 | Sep 22 – Sep 29 | 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 | Jan 7 – Jan 21 | — | Jan 28 – Feb 11 | Sep 22 – Oct 6 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Jan 7 – Jan 21 | — | Feb 4 – Feb 18 | — | 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 28 – Feb 11 | — | Sep 8 – Sep 22 | 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 28 – Feb 11 | — | Sep 22 – Oct 6 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Jan 21 – Feb 4 | — | Oct 20 – Nov 3 | 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 28 – Feb 11 | — | Sep 22 – Oct 6 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Dec 17 – Dec 31 | — | Jan 28 – Feb 11 | — | 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 3 – Nov 17 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Jan 28 – Feb 11 | — | — | 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 | — | — | Mar 11 – Mar 25 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Jan 28 – Feb 11 | — | 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 14 – Jan 21 | — | Mar 4 – Mar 11 | — | 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 | — | Feb 4 – Feb 18 | — | Oct 6 – Oct 20 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Dec 31 – Jan 14 | — | Feb 11 – Feb 18 | — | 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 | — | Feb 4 – Feb 18 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Dec 31 – Jan 14 | — | Feb 25 – Mar 4 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Dec 31 – Jan 14 | — | Feb 25 – Mar 4 | — | 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 | — | Mar 4 – Mar 18 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Jan 28 – Feb 4 | Mar 4 – Mar 18 | Mar 4 – Mar 11 | — | 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 14 – Jan 28 | — | Mar 4 – Mar 11 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Jan 28 – Feb 4 | Mar 4 – Mar 18 | Mar 4 – Mar 11 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Mar 4 – Mar 18 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Mar 4 – Mar 18 | — | 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 Santa Rosa, CA?
Based on 1991–2020 NOAA climate normals for the SANTA ROSA, CA US station, the last spring frost in Santa Rosa typically falls around February 25. A cautious gardener might wait until March 29 (only a 10% chance of a later frost), while January 21 marks an earlier, higher-risk planting date.
When is the first frost in Santa Rosa, CA in fall?
The first fall frost in Santa Rosa typically arrives around December 1. To stay safe, assume frost could start as early as November 10; in milder years it can hold off until December 24.
How long is the growing season in Santa Rosa, CA?
Santa Rosa's average frost-free growing season is about 279 days, running from the typical last spring frost (February 25) to the typical first fall frost (December 1).
What USDA hardiness zone is Santa Rosa, CA in?
Santa Rosa, 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.