Arizona Planting Guide & Growing Season
Arizona is in USDA hardiness zone 4b-10b with a growing season of 260 days. The average last spring frost is Mar 1 and the average first fall frost is Nov 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) | 4b-10b | Mar 1 | Nov 15 | 260 |
| Alabama (AL) | 7a-8b | Mar 15 | Nov 5 | 235 |
| Alaska (AK) | 1a-7b | May 30 | Sep 5 | 100 |
| Arkansas (AR) | 6b-8a | Apr 1 | Oct 25 | 210 |
| California (CA) | 4b-11a | Feb 15 | Nov 30 | 290 |
| Colorado (CO) | 3b-7a | May 10 | Oct 1 | 145 |
Frequently Asked Questions About Gardening in Arizona
When should I start seeds indoors in Arizona?
In Arizona, the average last frost date is Mar 1. Start most seeds indoors 6-8 weeks before this date. The USDA hardiness zone for Arizona is 4b-10b, with a growing season of approximately 260 days.
What USDA hardiness zone is Arizona?
Arizona falls in USDA hardiness zones 4b-10b. 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 Nov 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 260 days, from the last frost (Mar 1) to first frost (Nov 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.