Frost Date Calculator

Find estimated last spring frost and first fall frost dates by USDA hardiness zone. Plan your garden planting window with confidence.

USDA Hardiness Zone

Risk Level

Tab to move between fields

Last Spring Frost

Apr 20

First Fall FrostOct 20

Growing Season180 days

Planting WindowApr 20 through Oct 20

How to Use This Calculator

Select your USDA Hardiness Zone (find yours at planthardiness.ars.usda.gov).
Choose your Risk Level: conservative (10% frost probability), moderate (50%), or aggressive (90%).
Review Last Spring Frost date, First Fall Frost date, Growing Season length in days, and the safe Planting Window.

What each input means

Identify Input Parameters
USDA Hardiness Zone = 6, Risk Level = 1 = 2 input(s) provided
Calculate Last Spring Frost
Apr 20 = Apr 20
Calculate First Fall Frost
Oct 20 = Oct 20
Calculate Growing Season
180 = 180

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