FrostDateCheck

Maricopa, AZ 85172 Frost Dates

When can you plant in Maricopa, AZ?

Zone 9a

Around 02/05 is the usual last spring frost, about 161 days away. The first fall frost typically arrives around 12/06, about 305 frost-free days later.

The USDA Plant Hardiness Zone Map puts Maricopa in Zone 9a (20 to 25°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.

What to do before the first frost

About 14 weeks of growing season left in Maricopa before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

How much risk comes with planting early here

02/05 is the middle of 30 years of NOAA records, not a promise. Plant by 01/05 and you're betting against frost in roughly 9 years out of 10. 02/28 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Maricopa compares

Maricopa's growing season runs about 305 days, ranking 3,727 of 40,283 US ZIP codes measured here, longest to shortest. Within AZ, it ranks 244 of 506.

Learn more

zone vs. frost date covers why Zone 9a and Maricopa's frost date answer different questions. the frost range covers how to read the range around Maricopa's dates instead of trusting one.