Frost Dates & Planting Calendar for Maricopa, AZ
Plan your garden around Maricopa, AZ's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.
Last Spring Frost
February 23
Safe Mar 15
Typical Feb 23
Risky Jan 29
First Fall Frost
November 24
Safe Nov 10
Typical Nov 24
Risky Dec 8
Growing Season
274 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 9a
Subtropical to frost-free — heat, not cold, is the main limit on what you can grow.
Data: NOAA station MARICOPA 4 N, AZ US, 6.4 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 29 – Jan 12 | — | Mar 2 – Mar 9 | — | 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 15 – Dec 29 | — | Mar 2 – Mar 16 | — | 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 15 – Dec 29 | — | Mar 9 – Mar 16 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Jan 26 – Feb 2 | Mar 2 – Mar 9 | Mar 2 – Mar 9 | — | 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 2 – Feb 9 | Mar 2 – Mar 16 | Mar 2 – Mar 9 | — | 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 26 – Feb 2 | Mar 2 – Mar 16 | Mar 2 – Mar 9 | — | 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 2 – Mar 16 | — | — | 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 26 – Feb 2 | — | Mar 9 – Mar 16 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Jan 26 – Feb 2 | — | Mar 9 – Mar 16 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Feb 23 – Mar 9 | — | — | 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 23 – Mar 9 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Jan 12 – Jan 26 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Jan 26 – Feb 9 | — | Sep 29 – Oct 13 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Jan 12 – Jan 26 | — | Sep 29 – Oct 13 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Jan 26 – Feb 9 | — | Sep 15 – Sep 29 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Jan 26 – Feb 9 | — | Oct 13 – Oct 20 | 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 2 – Feb 16 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Jan 5 – Jan 19 | — | Feb 2 – Feb 9 | Sep 22 – Sep 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 | Jan 5 – Jan 19 | — | Feb 9 – Feb 16 | Sep 15 – Sep 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 | Jan 5 – Jan 19 | — | Jan 26 – Feb 9 | Sep 15 – Sep 29 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Jan 5 – Jan 19 | — | Feb 2 – Feb 16 | — | 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 26 – Feb 9 | — | Sep 1 – Sep 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 26 – Feb 9 | — | Sep 15 – Sep 29 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Jan 19 – Feb 2 | — | Oct 13 – Oct 27 | 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 26 – Feb 9 | — | Sep 15 – Sep 29 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Dec 15 – Dec 29 | — | Jan 26 – Feb 9 | — | 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 | — | — | — | Oct 27 – Nov 10 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Jan 26 – Feb 9 | — | — | 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 9 – Mar 23 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Jan 26 – Feb 9 | — | 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 12 – Jan 19 | — | Mar 2 – Mar 9 | — | 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 2 – Feb 16 | — | Sep 29 – Oct 13 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Dec 29 – Jan 12 | — | Feb 9 – Feb 16 | — | 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 2 – Feb 16 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Dec 29 – Jan 12 | — | Feb 23 – Mar 2 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Dec 29 – Jan 12 | — | Feb 23 – Mar 2 | — | 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 2 – Mar 16 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Jan 26 – Feb 2 | Mar 2 – Mar 16 | Mar 2 – Mar 9 | — | 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 12 – Jan 26 | — | Mar 2 – Mar 9 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Jan 26 – Feb 2 | Mar 2 – Mar 16 | Mar 2 – Mar 9 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Mar 2 – Mar 16 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Mar 2 – Mar 16 | — | 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 Maricopa, AZ?
Based on 1991–2020 NOAA climate normals for the MARICOPA 4 N, AZ US station, the last spring frost in Maricopa typically falls around February 23. A cautious gardener might wait until March 15 (only a 10% chance of a later frost), while January 29 marks an earlier, higher-risk planting date.
When is the first frost in Maricopa, AZ in fall?
The first fall frost in Maricopa typically arrives around November 24. To stay safe, assume frost could start as early as November 10; in milder years it can hold off until December 8.
How long is the growing season in Maricopa, AZ?
Maricopa's average frost-free growing season is about 274 days, running from the typical last spring frost (February 23) to the typical first fall frost (November 24).
What USDA hardiness zone is Maricopa, AZ in?
Maricopa, AZ is in USDA plant hardiness zone 9a, 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.