Improving Clay Soil in Arizona

Improving Clay Soil in Arizona

If you are searching “improving clay soil” because you are trying to grow a better landscape or garden in Arizona, this article is for you. It is normal for low desert soils to have high clay content, high pH, and low organic material. This leads to soil which is very alkaline, or salty.

High clay content does help the soil retain nutrients and water yet can stare it of oxygen and makes digging holes more difficult. In contrast some areas have sandy soil which also contains low organic material and will not hold moisture.

Working With Mother Nature

Classifications of soil like clay, sand, or silt are a reference to the texture of the soil, which is just about impossible to change. Instead of trying to fight Mother Nature and her desert landscape Arizona gardeners can choose plants which are accustomed to the conditions and will grow well. Choosing plants for your garden that prefer the acidic and loose soils of the eastern United States usually ends with frustration and choosing replacement plants.

Organic Material & Arizona

While a lot of gardening guides recommend the enrichment of soil with lots of organic material which adds nutrients to the soil and improves water retention and penetration, it is not ideal for Arizona. Other regions benefit from such treatments but here the alkaline soils cause organic material to decompose much more rapidly which can actually harm your plants.

Where it should be used

Mulch can and should be used in Arizona landscapes, just not IN the soil. It is a great addition to top the layers of your soil which will provide temperature regulation, help retain moisture, and reduce the growth of weeds.

How it should be used

Mulch can be spread out so it extends to the same diameter of the branches in a layer which is about 2 to 3 inches deep. Avoid letting organic material making direct contact with stems or the trunks of trees. If plants are desired which prefer the acidic soils of the eastern United States it is best to grow them in large containers where the soil’s makeup can be closely monitored and adjusted.

Mulch for vegetable gardens & flower beds

Vegetables and flowers are exceptions to being potentially damaged by rapid decomposition of organic matter in your soil. You can incorporate the organic materials each year by adding 3 inches of it into the soil and mixing it thoroughly.

Types of Organic Material

There are a lot of various organic materials which can be used to help gardens in Arizona. Many of them we either already have on hand or can purchase inexpensively from local nurseries.


Mulch is a combination which includes clippings from yards and other common waste products from homes. This can include leaves, grass clippings, hay, scraps from the kitchen, straw, sawdust, shredded newspaper, woodchips, cardboard and more.


While leaves are a common ingredient in mulch they fall naturally around our yards and plants. Leaving them when they lay under your plants provides incredible nutrient value. As they naturally decompose on the surface of the soil the nutrients will be added to your soil slowly.


You can make your own or buy it as your local nursery. It is typically made from produce waste or leaves which helps provide moisture retention but doesn’t carry with it excessive nutrients.


While it can be very beneficial to your plants it must be from the right animals and aged properly. It should come from vegetable eating animals like cows, horses, sheep, chickens or rabbits and have been aged for 6 months to a year.

Shredded Bark

Shredded bark is a popular landscaping material which provides a layer of protection from the sun and helps hold in some moisture on incredibly hot days. You can purchase it as your local nursery or if you have had a tree removed you might have some on hand.

Phoenix Valley Nurseries

If you live in the Phoenix valley and want to make the most of your landscape and garden A&P Nursery is here to help. We grow our plants right here in the East Phoenix Valley and sell them at 4 locations. Our team of nursery staff and expert gardeners love to help Arizona residents learn about what grows best, how to make that happen, and help equip gardeners with the best knowledge and tools available. Call or visit one of our 4 locations in the East Valley for more information or to get your garden started.

Leave a Reply

Your email address will not be published. Required fields are marked *