When to Plant Kale in Arizona
The toughest green in the garden. Kale laughs at frost and actually tastes sweeter after a cold snap.
The Short Answer
Arizona Frost Dates
Your planting dates depend on which part of Arizona you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Arizona (Flagstaff) | 4b, 5a, 5b, 6a | May 15 - Jun 5 | Sep 15 - Oct 10 |
| Central Arizona (Phoenix) | 9a, 9b, 10a | Jan 15 - Feb 10 | Dec 1 - Dec 20 |
| Southern Arizona (Tucson) | 8b, 9a, 9b | Feb 1 - Feb 25 | Nov 20 - Dec 15 |
Kale Planting Schedule for Arizona
Northern Arizona (Flagstaff) (Zones 4b, 5a, 5b, 6a)
Average last frost: May 15 - Jun 5 · Average first frost: Sep 15 - Oct 10
Central Arizona (Phoenix) (Zones 9a, 9b, 10a)
Average last frost: Jan 15 - Feb 10 · Average first frost: Dec 1 - Dec 20
Southern Arizona (Tucson) (Zones 8b, 9a, 9b)
Average last frost: Feb 1 - Feb 25 · Average first frost: Nov 20 - Dec 15
Growing Kale in Arizona
Kale in Arizona's Climate
Grow kale from November through February. The window is shorter than in moderate climates but productive. Kale handles Florida's occasional frost better than most cool-season crops. Once spring temperatures climb consistently above 80°F, kale bolts and becomes bitter.
Soil Considerations for Arizona
Alkaline, mineral-rich desert soils. Low organic matter. Heavy amendment with compost essential. Caliche layers may need to be broken.
Arizona Climate & Growing Season
Extreme heat in summer lowlands. Two planting seasons in Phoenix — spring and fall (summer is too hot). High elevation has traditional cold-climate seasons. Kale can handle frost well, which is an advantage in Arizona's climate. You can push planting dates earlier in spring and extend into fall.
Growing season length varies across Arizona: Northern Arizona (Flagstaff) (4b, 5a, 5b, 6a) has a last frost around May 15 - Jun 5, while Southern Arizona (Tucson) (8b, 9a, 9b) sees frost end around Feb 1 - Feb 25. This difference matters for kale — adjust your planting dates to match your specific region.
Growing Tips
Harvest outer leaves first, leaving the center to keep growing. Can survive temperatures down to 10°F with mulch protection.
Companion Planting
Plant kale alongside these companions for better growth:
Keep kale away from:
The Bottom Line
Last reviewed: March 29, 2026