Extreme Weather Gardening

Newly Pruned Mesquite--thinned and the canopy raised

Luckily, there are not many gardening chores necessary during the intense heat of Arizona desert summers, at least not in my landscape, which consists mostly of desert adapted trees and shrubs. I said mostly because I do have some roses and a few other plants that do take some extra care, and a lot of potted cacti and succulents that require extra watering.


This year has been especially rough for even the desert adapted plants. Little rain, the hottest July on record, and sun intensity has been stronger than ever due to little cloud cover. So far, the monsoon season is a bust. That's good in one sense--no violent wind or dust storms or downed trees to contend with, but supplemental watering and shade cloth on some things is a must.


I don't get up early, so any gardening I do is accomplished just around sunset, and I'll work outside for awhile each day until it's late dusk. Unlike my husband, I can't take the heat for any period of time, even in the evening. Pretty wimpy for an Arizona native--but I'm just not acclimated to summer sun exposure anymore because of home and car air conditioning.


Recently, a reader named Bonnie left a comment asking what kind of garden chores I do this time of year. She felt she should be doing something despite the heat. My answer is--do as little as possible, but I have listed a few things that I do accomplish.


I usually mix up cactus potting soil so that it will be ready for any October potting that I do. The mix I use is 1/3 river wash sand, 1/3 pumice, and 1/3 native soil. I also use an alternative--mixing native soil and potting soil in equal proportions to make one part, then one part pumice and one part river wash sand. Proportions should be adjusted depending on whether the native soil is clay heavy.


Contrary to information provided by many sources that say not to prune desert trees in their growth period because it causes undue stress and weak wood from the rapid growth, the hottest months are actually an ideal time prune. According to a recent study by the University of Arizona, desert trees recover from pruning better in the summer because of the fact they grow quickly and they heal better in the heat. I usually water the trees right after a heavy pruning to lessen stress. It's always worked for me, so I was happy to read that studies support my practices.


It seems there's always a few dead perennials, cacti and succulents to dispose of this time of year. Once I clean up the debris, I plug the irrigation emitters and put a small landscape flag in the gravel to mark the spot for replacement planting in the fall.

Add required shade cloth protection. I have only four plants in my garden that require this protection, which I put down in early June. I use 35 percent and 50 percent shade cloth, depending on the plant. Once the shade cloth is in place, I don't need to do much more except make sure it's adjusted as the sun changes angles the rest of the summer. I remove it, gradually, in mid September. Many other cacti and succulents receive some sun scorch each year, but it's not permanent and they'll recover in fall. The plants I cover are ones that will be permanently injured if they didn't have shade cloth protection.

 Summer is the time to decide on wildflower mix purchases because September and October are the ideal months for wildflower seed distribution in desert landscapes. Wild Seed, a company in Tempe, Arizona, has great wildflower mixes. They do not have a web site or take credit cards, so you have to order the old fashioned way--with a form and pay with a check or money order.

Roses need extra watering this time of year, and regular foliage spraying helps them with heat stress in early morning (not me) or late afternoon. Other than that, the only other chore is dead heading and making sure the mulch in their planting beds remains evenly distributed and thick enough.

One other thing I do in summer is paint one rock to add to my collection. This is a long standing, enjoyable ritual that I save for summer and wrote about last year.