This coming Friday I retire from my position as a Pinal County Cooperative Extension agent.
On April 27, 1981, I walked into the University of Arizona Cooperative Extension office at the then new Pinal County office complex on Cottonwood Lane to begin my career. I was ushered into an office and given a pencil and a pad of paper. On that day, I took my first gardening call and just a few weeks later I taught my first gardening class in Kearny, over on the eastern side of the county. I remember being slightly tongue-tied for the first few seconds of both, but it did not last for long. I was trained in the science and I took to the work like a thirsty gardener to a long drink of cool water. I had found my niche.
A few weeks later, after I had settled into the new job, I was invited to write a gardening column for this newspaper, and I accepted the invitation. In those days before computers, I wrote it long hand and hand carried a typed version down to the newspaper office. Today, it is all done electronically. How things have changed. I wrote the column for a couple of years, and then, for some reason, I got busy on something else, and I let the column go. Then, about 20 years ago, I was again approached, and it has been my privilege to write a weekly garden and landscape column in this space ever since. I have enjoyed the task.
We have spoken here about many topics, you and I, and each of them was related somehow to gardening in the desert. One of my friends recently asked if I were about to run out of topics. My answer was “No, there is always plenty to write about.” Most commonly, however, I always seemed led to write about something that would help a newcomer learn to garden in the desert, to get over that hump between success and failure.
Many new to the Sonoran Desert find that the local environment provides challenges for plants that really are unheard of in other parts of the country. Things just are different here. Often the recommended practices successful in other locations simply do not work in the desert. After initial results, usually depressing, of trying to grow a garden, many people wonder if anything can work. My response has always been that if we understand the basic principles of desert gardening, we can be successful. As evidence of this, I point to you, the experienced gardeners, and the wonderful results that you have achieved in your gardens.
Since this will be my last column, perhaps it might be helpful to summarize just a few of the most important of these desert gardening principles. If you have any questions, I refer you to the highly experienced Cooperative Extension Master Gardener volunteers scattered over the entire county who are standing by to assist. They are well trained and certified by the University of Arizona. You can find their contact information at the end of this article.
The first principle relates to the climate itself. To ensure gardening success, we need to work with it as a partner instead of fighting against it in never-ending conflict. The Sonoran Desert is what it is, and it will not change. To be successful in growing plants, we need to acknowledge that its rules are supreme.
Let’s consider planting dates as an example. Planting dates for annual flowers and vegetables must be understood and followed. If we plant sweet corn on a day that will allow it to be “knee-high by the Fourth of July,” as is done elsewhere, here we will have nothing to show at harvest but blasted ears and only a few kernels scattered here and there on the cob. The heat of summer sterilizes the pollen so that fertilization does not occur. Instead, we plant no later than March 15 to ensure that the new kernels are set and growing before hot weather appears. We then can harvest in late May or early June. Other plants have their own preferred planting dates.
Another critical principle is the choice of plant varieties. There are many “favorite” varieties from which to choose but if we select one that does not do well here, even if it is excellent in other parts of the country, plant failure is common. Plants not adapted will turn brown with the salt and heat. Fruiting plants fail to produce. Many plants not adapted to the desert will simply die.
I hope that you will remember that we spoke about the proper way to plant a tree or shrub. A hole for planting a tree should only be as deep as the container but three to five times as wide. It used to be said that the perfect planting hole was 4 feet wide on all sides and 4 feet deep. We have moved away from that recommendation because we found that the loosened soil below the root ball tended to collapse downward as the air pockets in the soil worked themselves out. This resulted in the entire plant sinking low into the ground with trunk tissue that should have been exposed to air now buried in soil. That kind of thing usually ends badly for the plant.
Please remember that pruning back large branches, called “stub pruning” in the horticultural business, is not, repeat not, the correct way to treat a tree. Cutting off large branches to solve a problem will only result in opening a freeway for insects and diseases to gain entry into the tree. In addition, stub pruning cuts away and discards much of the stored energy the plant was able to create and hide away for future needs. The energy from photosynthesis does not get stored in the leaves because those will eventually fall off the plant. Energy gets stored in the branches, trunk and roots where it can be protected until it is needed. Cutting off major branches simply throws much of this hard effort into the landfill and new branches that grow back will be weakly attached. This could lead to breakage in a windstorm. Please resist the urge to stub prune.
Most plant problems in the desert are caused by non-living factors and not by living organisms. It is a common practice when something goes wrong in the garden to look for insects or diseases as the culprit. Sometimes they are. However, most problems are caused not by insects or diseases but by nonliving conditions. Heat or cold, salts in the soil and water, chemical injury and mechanical damage from lawn mowers or string trimmers take a greater toll among plants than the insects of the diseases. Interestingly enough, most abiotic factors are things that we as gardeners can control. Good management will solve a lot of problems.
Water must be provided to all plants in the yard to keep them happy. Some require more than others. We must be careful to provide just the right amount at the right times to ensure that they do not become stressed for water, either too much or too little. Even a saguaro, that normally can get by on rainfall alone, may need an occasional drink during an extended drought. Ironwood and palo verde trees also use a minimum of water, while a mesquite may require a little more. A citrus or an ash tree needs regular water to keep it happy. We must understand the water needs of the plant and provide what it needs in a timely manner, if we want to keep it alive and thriving in our yards.
It has been a fun 39 years, and I have learned a lot as I have served in my position. I was asked recently what I have most enjoyed about my career. I can instantly say in all seriousness that it has been the interaction with people across this county, state and nation. Those interactions have been the highlight of my career.
I wish to take this opportunity, as I conclude, to thank the owners, editors and staff of Casa Grande Valley Newspapers Inc. for inviting me to write that first column so many years ago, and for accepting my material through the years. I especially want to thank you, the readers, and all of the people with whom I have been able to work, for allowing me to share science-based information as we have worked together to solve plant problems. Thanks for the fun.
If you have questions, you can reach one of our Master Gardener volunteers every day except Saturday and Sunday between 9 a.m. and noon by calling the Master Gardener hotline at 520-374-6263. You can also call the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande at 520-836-5221, ext. 204 and leave a message.