Arizona Planting Guide & Growing Season
Arizona is in USDA hardiness zone with a growing season of 270 days. The average last spring frost is Feb 1 - Apr 15 and the average first fall frost is Oct 15 - Dec 15. Climate data based on Phoenix.
Growing Conditions in Arizona
How Arizona Compares
Compare Arizona's growing conditions with states that have similar climates.
| State | USDA Zone | Last Frost | First Frost | Season (days) |
|---|---|---|---|---|
| Arizona (AZ) | Feb 1 - Apr 15 | Oct 15 - Dec 15 | 270 | |
| Alabama (AL) | Mar 1 - Apr 1 | Oct 25 - Nov 15 | 220 | |
| Alaska (AK) | May 15 - Jun 15 | Aug 15 - Sep 15 | 105 | |
| Arkansas (AR) | Mar 15 - Apr 15 | Oct 15 - Nov 1 | 210 | |
| California (CA) | Jan 15 - Apr 15 | Oct 15 - Dec 31 | 290 | |
| Colorado (CO) | Apr 15 - Jun 1 | Sep 15 - Oct 15 | 150 |
Frequently Asked Questions About Gardening in Arizona
When should I start seeds indoors in Arizona?
In Arizona, the average last frost date is Feb 1 - Apr 15. Start most seeds indoors 6-8 weeks before this date. The USDA hardiness zone for Arizona is undefined, with a growing season of approximately 270 days.
What USDA hardiness zone is Arizona?
Arizona falls in USDA hardiness zones undefined. This affects which perennial plants will survive winter and influences optimal planting times.
When is the first frost in Arizona?
The average first frost date in Arizona is Oct 15 - Dec 15. Plan to harvest cold-sensitive crops before this date or protect them with row covers.
How long is the growing season in Arizona?
Arizona has an average growing season of 270 days, from the last frost (Feb 1 - Apr 15) to first frost (Oct 15 - Dec 15). This long season supports warm-season crops like tomatoes, peppers, and melons.
Plan Your Garden
Use our seed starting calculator to get personalized planting dates, or browse all states.