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Hardiness zones

Find your zone, then plant with confidence

A USDA hardiness zone is just a label for your average coldest winter temperature. Each numbered zone covers a 10°F band, and the a or b splits it into 5°F halves. That number is what sets your frost dates and how long your growing season runs, so it is the starting point for knowing when to plant.

Not sure which zone you are in?

Enter your ZIP code and we will find your USDA zone and your nearest weather station's frost dates, then build your planting calendar.

Browse by zone

Each zone page shows typical frost dates and the full planting year. Zones 3 through 10 are covered, where frost timing meaningfully changes what you plant and when.

Zone 3a-40°F to -35°F

Last frost May 29 · first frost September 5

Zone 3a planting guide →
Zone 3b-35°F to -30°F

Last frost May 17 · first frost September 23

Zone 3b planting guide →
Zone 4a-30°F to -25°F

Last frost May 12 · first frost September 28

Zone 4a planting guide →
Zone 4b-25°F to -20°F

Last frost May 8 · first frost October 1

Zone 4b planting guide →
Zone 5a-20°F to -15°F

Last frost May 3 · first frost October 5

Zone 5a planting guide →
Zone 5b-15°F to -10°F

Last frost May 1 · first frost October 10

Zone 5b planting guide →
Zone 6a-10°F to -5°F

Last frost April 29 · first frost October 16

Zone 6a planting guide →
Zone 6b-5°F to 0°F

Last frost April 23 · first frost October 22

Zone 6b planting guide →
Zone 7a0°F to 5°F

Last frost April 16 · first frost October 25

Zone 7a planting guide →
Zone 7b5°F to 10°F

Last frost April 5 · first frost November 1

Zone 7b planting guide →
Zone 8a10°F to 15°F

Last frost March 29 · first frost November 7

Zone 8a planting guide →
Zone 8b15°F to 20°F

Last frost March 17 · first frost November 14

Zone 8b planting guide →
Zone 9a20°F to 25°F

Last frost March 2 · first frost November 26

Zone 9a planting guide →
Zone 9b25°F to 30°F

Last frost February 1 · first frost December 9

Zone 9b planting guide →
Zone 10a30°F to 35°F

Last frost frost-free · first frost frost-free

Zone 10a planting guide →
Zone 10b35°F to 40°F

Last frost frost-free · first frost frost-free

Zone 10b planting guide →

USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service / Oregon State University PRISM Group. NOAA National Centers for Environmental Information, U.S. Climate Normals 1991-2020. Zone dates are medians across the zone; your town varies.