Frost Dates & Planting Calendar for Flowing Wells, AZ
Plan your garden around Flowing Wells, 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 11
Safe Mar 7
Typical Feb 11
Risky Jan 16
First Fall Frost
December 2
Safe Nov 16
Typical Dec 2
Risky Dec 20
Growing Season
293 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 TUCSON U OF A #1, AZ US, 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 17 – Dec 31 | — | Feb 18 – Feb 25 | — | 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 3 – Dec 17 | — | Feb 18 – Mar 4 | — | 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 3 – Dec 17 | — | Feb 25 – Mar 4 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Jan 14 – Jan 21 | Feb 18 – Feb 25 | Feb 18 – Feb 25 | — | 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 21 – Jan 28 | Feb 18 – Mar 4 | Feb 18 – Feb 25 | — | 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 14 – Jan 21 | Feb 18 – Mar 4 | Feb 18 – Feb 25 | — | 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 18 – Mar 4 | — | — | 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 14 – Jan 21 | — | Feb 25 – Mar 4 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Jan 14 – Jan 21 | — | Feb 25 – Mar 4 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Feb 11 – Feb 25 | — | — | 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 11 – Feb 25 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Dec 31 – Jan 14 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Jan 14 – Jan 28 | — | Oct 7 – Oct 21 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Dec 31 – Jan 14 | — | Oct 7 – Oct 21 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Jan 14 – Jan 28 | — | Sep 23 – Oct 7 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Jan 14 – Jan 28 | — | Oct 21 – Oct 28 | 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 21 – Feb 4 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Dec 24 – Jan 7 | — | Jan 21 – Jan 28 | Sep 30 – Oct 7 | 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 24 – Jan 7 | — | Jan 28 – Feb 4 | Sep 23 – Sep 30 | 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 24 – Jan 7 | — | Jan 14 – Jan 28 | Sep 23 – Oct 7 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Dec 24 – Jan 7 | — | Jan 21 – Feb 4 | — | 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 14 – Jan 28 | — | Sep 9 – Sep 23 | 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 14 – Jan 28 | — | Sep 23 – Oct 7 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Jan 7 – Jan 21 | — | Oct 21 – Nov 4 | 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 14 – Jan 28 | — | Sep 23 – Oct 7 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Dec 3 – Dec 17 | — | Jan 14 – Jan 28 | — | 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 4 – Nov 18 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Jan 14 – Jan 28 | — | — | 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 25 – Mar 11 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Jan 14 – Jan 28 | — | 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 31 – Jan 7 | — | Feb 18 – Feb 25 | — | 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 21 – Feb 4 | — | Oct 7 – Oct 21 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Dec 17 – Dec 31 | — | Jan 28 – Feb 4 | — | 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 21 – Feb 4 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Dec 17 – Dec 31 | — | Feb 11 – Feb 18 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Dec 17 – Dec 31 | — | Feb 11 – Feb 18 | — | 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 18 – Mar 4 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Jan 14 – Jan 21 | Feb 18 – Mar 4 | Feb 18 – Feb 25 | — | 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 31 – Jan 14 | — | Feb 18 – Feb 25 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Jan 14 – Jan 21 | Feb 18 – Mar 4 | Feb 18 – Feb 25 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Feb 18 – Mar 4 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Feb 18 – Mar 4 | — | 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 Flowing Wells, AZ?
Based on 1991–2020 NOAA climate normals for the TUCSON U OF A #1, AZ US station, the last spring frost in Flowing Wells typically falls around February 11. A cautious gardener might wait until March 7 (only a 10% chance of a later frost), while January 16 marks an earlier, higher-risk planting date.
When is the first frost in Flowing Wells, AZ in fall?
The first fall frost in Flowing Wells typically arrives around December 2. To stay safe, assume frost could start as early as November 16; in milder years it can hold off until December 20.
How long is the growing season in Flowing Wells, AZ?
Flowing Wells's average frost-free growing season is about 293 days, running from the typical last spring frost (February 11) to the typical first fall frost (December 2).
What USDA hardiness zone is Flowing Wells, AZ in?
Flowing Wells, 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.