Yuma, Arizona: planting zone & frost dates
Yuma is in USDA plant hardiness zone 9a, where the average coldest winter night reaches 20 to 25°F (-6.7 to -3.9°C). Frost is rare here.
Frost dates
Frost data comes from NOAA station YUMA MCAS, AZ (USW00003145), 10.7 mi (17.3 km) from the city center and 43 ft lower than the city center (-13 m). Record used for the 1991–2020 normals: 27 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Yuma
Yuma spans more than one half-zone. Share of the city's land area by zone (via its 2 ZIP codes): 9a (77%), 10a (23%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.
Vegetable planting calendar for Yuma
Windows below are for a frost-free climate: plant cool-season crops from fall through late winter and warm-season crops in late winter–spring, with a second warm-season round in late summer for some crops.
| Crop | Planting windows (frost-free climate) | |||
|---|---|---|---|---|
| Tomato | Jan 15 – Mar 31; Aug 1 – Sep 15 | |||
| Pepper | Feb 1 – Apr 15; Jul 15 – Aug 31 | |||
| Lettuce | Sep 15 – Feb 15 | |||
| Green Beans | Feb 15 – Apr 30; Aug 15 – Sep 30 | |||
| Sweet Corn | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| Zucchini & Summer Squash | Feb 15 – Apr 15; Aug 1 – Sep 15 | |||
| Cucumber | Feb 15 – Apr 15; Aug 1 – Sep 15 | |||
| Carrot | Sep 1 – Feb 28 | |||
| Onion | Oct 15 – Jan 15 | |||
| Potato | Jan 1 – Feb 28; Sep 1 – Oct 15 | |||
| Basil | Mar 1 – Jun 30; Aug 15 – Sep 30 | |||
| Spinach | Oct 1 – Feb 15 | |||
| Kale | Sep 1 – Feb 15 | |||
| Broccoli | Sep 1 – Jan 15 | |||
| Peas | Oct 1 – Jan 31 | |||
| Eggplant | Feb 15 – Apr 30; Jul 15 – Aug 31 | |||
| Cabbage | Sep 1 – Jan 31 | |||
| Radish | Sep 15 – Mar 15 | |||
| Strawberry | Oct 1 – Nov 30 | |||
| Beets | Sep 15 – Feb 28 | |||
Nearby cities in Arizona
- Buckeye — zone 9b, last frost Jan 18, first frost Dec 16
- Goodyear — zone 9b, last frost Jan 29, first frost Dec 12
- Avondale — zone 9b, last frost Jan 18, first frost Dec 16
- Surprise — zone 9b, last frost Feb 16, first frost Dec 2
- Glendale — zone 9b, last frost Feb 2, first frost Dec 8
- Peoria — zone 9b, last frost Feb 16, first frost Dec 2
More: all Arizona cities · other zone 9a cities: San Antonio, TX, Austin, TX, Seattle, WA, Las Vegas, NV, Portland, OR, Tucson, AZ, Baton Rouge, LA, Tallahassee, FL
Yuma gardening questions
Does it ever frost in Yuma, AZ?
Rarely. From 1991 to 2020, NOAA's Yuma Mcas, AZ station, 10.7 mi from the city center, reached 32°F in only 8% of years — too seldom for NOAA to compute frost dates. Zone 9a means the coldest night of an average winter is 20 to 25°F (-6.7 to -3.9°C), so tender plants may still need covering in an unusual cold snap.
When should I plant tomatoes in Yuma, AZ?
Without a frost season, plant by temperature: set out tomatoes Jan 15 – Mar 31 and Aug 1 – Sep 15. Fruit set drops when nights stay above about 75°F, so avoid timing harvests for the hottest weeks. More: tomato planting by zone.
When is the best time for lettuce and broccoli in Yuma?
Cool-season crops do best in the mild months: plant lettuce Sep 15 – Feb 15 and broccoli Sep 1 – Jan 15. Summer heat makes lettuce bolt and broccoli flower early.
Did Yuma's hardiness zone change on the 2023 map?
Yes, but toward colder: Yuma went from zone 10a (2012) to zone 9a (2023). Only about 1% of U.S. ZIP codes moved colder; these changes mostly reflect added weather stations and improved mapping methods rather than a colder climate. Why the 2023 map is warmer.
Is all of Yuma in zone 9a?
No. Zone 9a covers about 77% of the city's land; the rest is in 10a (23%), measured across the city's 2 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.