Regional Climate Guide

Plant by your zone, then check the region

A USDA zone screens winter cold tolerance. Your region adds summer heat, rainfall, frost timing, wind, soil, and the length of the usable season.

Choose a zone Open the official USDA map

US Growing Regions

Regions that include Zone 10

Two yards can share a hardiness number while receiving different rain, summer heat, wind, and frost windows.

3 regions

Zones 7–10

Southeast

0°F to 40°F

Long, hot, humid summers meet mild winters. Plant choice depends as much on disease resistance and heat tolerance as winter survival.

Rainfall: 45–65 inches annually
Growing season: 240–365 days
Winter low: 25°F to 40°F
Summer high: 85°F to 95°F

Conditions to plan around

Fungal disease in humidity
Tropical storm damage
Heat stress on cool-season plants
Heavy clay soils

Regional footprint

North Carolina, South Carolina, Georgia, Florida, Alabama, Mississippi, Louisiana, Tennessee, Arkansas

Plants that show the regional range

Crape MyrtleZone 7–9

St. Augustine GrassZone 8–10

AzaleaZone 5–9

Southern MagnoliaZone 7–10

Zones 8–10

Southwest

10°F to 40°F

Heat, low rainfall, alkaline soil, and intense sun drive plant choice. Water strategy matters more than a mild zone number suggests.

Rainfall: 8–15 inches annually
Growing season: 270–365 days
Winter low: 25°F to 40°F
Summer high: 95°F to 110°F

Conditions to plan around

Extreme heat and drought
Alkaline soils
Intense UV
Flash flooding
Limited water

Regional footprint

Arizona, New Mexico, Nevada, West Texas, Southern California

Plants that show the regional range

Blue AgaveZone 9–11

Desert MarigoldZone 8–10

Texas SageZone 7–10

Red YuccaZone 5–10

Zones 8–11

California

10°F to 50°F

Mediterranean rainfall patterns and strong local microclimates make summer water, elevation, coast exposure, and fire conditions decisive.

Rainfall: 10–40 inches annually
Growing season: 300–365 days
Winter low: 35°F to 50°F
Summer high: 75°F to 100°F

Conditions to plan around

Summer drought
Wildfire risk
Water restrictions
Variable soil
Coastal fog and salt

Regional footprint

California

Plants that show the regional range

California PoppyZone 6–10

LavenderZone 5–9

Coast Live OakZone 9–10

Blue FescueZone 4–8

USDA Reference

Read the winter temperature bands

Each full zone spans 10°F. Local a and b subzones divide that band into 5°F steps.

Temperature based

The number comes from average annual extreme minimum temperature, not an average winter day.

Useful for perennials

Trees, shrubs, and returning perennials need a winter band that matches their cold tolerance.

One part of the site

Summer heat, humidity, rainfall, drainage, and microclimates can still remove a plant from the shortlist.

Zone 1Below -50°F Zone 2-50°F to -40°F Zone 3-40°F to -30°F Zone 4-30°F to -20°F Zone 5-20°F to -10°F Zone 6-10°F to 0°F Zone 70°F to 10°F Zone 810°F to 20°F Zone 920°F to 30°F Zone 1030°F to 40°F Zone 1140°F to 50°F Zone 1250°F to 60°F Zone 1360°F to 70°F

Frost Calendar