The best time to plant trees is right now
Cooler weather allows roots to grow and get established before it gets hot
If you are new to desert living, you may not know that now is a good time for planting trees and shrubs. In fact, the ideal planting time is from September to April. Throughout the cooler months, the roots can grow, allowing the plants to establish themselves before summer heat.
Look at the area where you are planning to put the new tree or shrub. Make sure the amount of sunlight the site receives matches the amount the plant requires. Do check the site because, believe it or not, there is shade in the desert!
Some tags on the plant will say "Full Sun," but that is not taking into account the kind of sunny days we have, with temperatures above 100 degrees. Determine which plants will thrive in your particular area. Full sun, partial shade, or full shade will really determine the success of your newly acquired plant. Reflected heat from walls may be too extreme for many plants, even some desert natives.
Also, cold air collects in low areas of your yard and frost-sensitive plants may be damaged in these locations.
Consider the eventual height and width of the mature plant. Visualize what it will look like in 10-15 years. I bet you all know someone, possibly yourself, who placed a tree too close to the house and regretted it. Many trees grow to overpower or may endanger the homes they are near. Many shrubs that are placed too close to foundations rub against exterior walls and cause structural damage. Placing the "right plant in the right place" will prevent continual maintenance or replacement.
Remember that trees and shrubs can take years to develop into the specimens you see in pictures. Growing times vary. Don't think that planting a large plant will give you a large tree sooner. Generally, a smaller plant will outgrow a larger one within a short time span. Plants that grow too quickly may have weak wood, making them vulnerable to wind or storm damage.
Soil here is mostly alkaline (salty) with a pH of almost 8 with a high clay content. The low humidity levels and high air temperatures cause soil here to evaporate quickly. Look for plants that can tolerate these soil conditions and temperature extremes.
Several trees that are happy with these growing conditions are Az Cypress, Desert Willow, Texas Mesquite and Western Redbud. Shrubs that are proven growers here are Apache Plume, Brittle Bush, Creosote Bush and Desert Cassia.
You have selected the plant and the site. Let's plant! First, apply water to the area where you will be planting several days ahead of time. This will make digging much easier. The soil should be moist but not wet. It should not stick to the shovel.
Loosen the soil 4-5 times the diameter and no deeper than the root ball. Roots that absorb water and nutrients will grow rapidly in the area, so your plant can establish itself quickly.
Remove soil in the center to create the hole. It should be twice as wide but only as deep as the root ball. This prevents sinking which can bury the stem or trunk. The bottom of the hole should be flat.
Check drainage by filling the hole with water. If water can penetrate the soil, so can plant roots. If water has not drained in 24 hours, a chimney can be added for drainage.
If you are not sure where your utility lines are located, call the utility company prior to digging any holes. Be sure to look overhead and think about the height of the mature tree. Will it interfere with overhead power lines?
Always handle the plant by the container or root ball, and never by the trunk. Always place the plant at the same level as it was in the container. Do not pile soil up on the trunk or stems and do not plant too deep. The top of the root ball should be level or slightly above the soil surface. Backfill with native soil. No fertilizer or amendments are necessary at this time. Use the soil you removed when you dug the hole. This will encourage a strong root system and a healthier plant.
Are you done? NO! These last steps can make a huge difference between a healthy plant or a spindly one. Pruning is not recommended except to remove broken or dead branches. Allowing lower branches on the tree the first year promotes strong trunks and healthy growth. It also reduces the risk of sunburn.
Watering is not an option. You must water well when planting. Create an area around the plant to collect water. Apply enough water to thoroughly wet the soil to the depth of the root ball.
Apply a layer of organic mulch from 2-4 inches on top of the soil. Keep it away from the stem or trunk. Mulching slows evaporation and keeps the soil cooler. As organic mulch decomposes, it adds nutrients back into the soil.
Follow these steps and your new addition will give you years of pleasure.