ARIZONA PLANT CLIMATE ZONES
BY CATHY RYMER, CERTIFIED ARBORIST
The climate zones of Arizona are as varied as our region,
ranging from sub-alpine to tropical desert. Before planting
trees in our state, it's important to know how local climate
affects plant growth. In addition to the minimum
temperatures that trees can withstand, be sure to make
note of varying conditions in your area such as reflected
heat or high humidity. These are referred to as micro
climates that take into consideration factors like sun
exposures, wind or airflow, humidity, soil, paved areas,
shade, structures and even hills and valleys.
The climate zones listed below are those used by Sunset.
Sunset's climate zones consider temperature as well as
other important factors including the total climate, length
of growing season, timing and amount of rainfall, winter
lows, summer highs, wind, and humidity. This is unlike the
USDA, which divides most of North America into zones
based strictly on winter lows.
The discussion of each climate zone lists several
appropriate trees. Climates of adjoining zones blend into
each other near their boundaries, making it possible to
grow some plants from each region. There will be many to
choose from and we encourage you to investigate the
choices. Geographical sites, cities and towns are included
as a reference for each zone.