SOIL 101 FOR ARIZONA WHAT YOU NEED TO KNOW BY EMILY ROCKEY
"I have such bad soil."
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erhaps you’ve heard this lamentation from Arizona residents, or maybe you’ve even thought it yourself. However, two of our state’s five “Cs” that represent major industries here—cotton and citrus—grow in Arizona soil; plus a third (cattle) depends upon the soil. Do we actually have “bad soil”? Or might it be that if we learn a little about desert soils, we would find greater understanding, and in turn, greater success in our gardening endeavors? What is “good soil”? There is no one-size-fits-all answer when it comes to soil, as it depends upon the preference of the plant. If you learn how a species grows in nature, and then mimic those conditions, you will likely find success. A saguaro cactus grows wild in the Sonoran Desert where soils are sandy and lack organic matter, and do not hold moisture between scarce rain events. On the other hand, a lush fern that grows wild in moist, cool forests with ample shade and rich soil would do very poorly where the saguaro cactus flourishes. The cacti and other Arizona native plants are adapted and designed
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to thrive in this soil and in the hot, arid conditions. To put a twist on the old saying, “To each plant their own soil.” Once we identify what we’d like to grow and what environmental conditions those plants prefer, we can start to build a soil. In our backyards we have Sonoran Desert soils, so the easiest plants to grow are those that are native to the area, where the conditions match the plants’ needs. But if you wish to grow a non-native vegetable garden, or a fruit tree, our native soil will perform well with just some soil amendments. Here is a guide.
FIND BALANCE IN THE SOIL Soil particles—sand, silt, and clay—should be balanced to allow water to drain, but not dry out so quickly that the plant is stressed for water.
AERATION IS KEY Many people do not know that air spaces in the soil are just as important as water retention. Plant roots need oxygen greenlivingaz.com
