Trees add beauty and shade to outdoor areas. And if you reside in the Southwest, you will agree that trees are highly valued because they bring a cooling effect during the long summer months. To maintain them, you must take care to water them properly.
During drought, deciduous trees in the Southwest cope well, but they need watering at intervals. So, when is the best time to irrigate, and how often should you do so? These are the questions this article will address. You may want to check out https://www.gardeningknowhow.com/ if you’re looking for shade trees for your Southwest home.
When Should You Irrigate Deciduous Trees in the Southwest?
Deciduous trees lose their leaves in fall so they can conserve moisture in winter. When this happens, avoid watering to prevent new growth that won’t survive in winter. The best time to irrigate deciduous trees is in late fall.
By this time, they are no longer shedding their leaves. But you must irrigate before the soil becomes frozen. If you wait till winter sets in, the soil will be too hard for any water to seep down the root zone.
Another critical period for irrigation is summer when the soil has exhausted the moisture from winter. Deciduous trees may not show signs of heat stress but they need deep watering at least once a week.
Lastly, irrigation is necessary during late winter, especially for new plants. This is when new buds and small roots begin to form. The roots require moist soil to develop as well as absorb nutrients and water for overall plant growth. Therefore, if the soil is too dry when the roots emerge, their chances of survival are slim. Many of them will even die before spring.
How to Irrigate Established Deciduous Trees
Water requirements for native Southwest trees vary, so you may want to contact a tree care company for professional guidance. However, below are some general irrigation tips.
Target the Drip Line
The drip line of a tree is also called the root protection zone. But it is quite a confusing gardening term. So, here’s a simple way to describe it.
When rain falls on an umbrella, it drips down the outer edges, forming a circle that is almost the same as the circumference of the umbrella. Now, imagine standing under a tree that has a dense canopy when it is raining. It will provide some protection from the rain.
Instead of the rain penetrating the branches, it drips to the ground, forming a circle around the canopy. This portion is called the drip line.
Large trees have widespread roots, which absorb water from the drip line. So, if you’re watering your tree close to the trunk, you’re doing more harm than good as it may rot. You may want to check out this website to learn more about watering the trunk.
Consider Slow Watering
Instead of watering the surface soil, trees will benefit more if the water gets to the roots directly. Slow watering or deep root watering is a technique that delivers water 6 to 12 inches into the soil. It reduces water loss due to evaporation and runoff.
You can use a soaker hose or install an extension to your drip irrigation system. This extension goes directly into the root zone, forming a soaker system.
Avoid Watering the Foliage
Although watering foliage can reduce the plant’s temperature, it can also make them lose moisture. When this happens, they become weak and prone to diseases. Overhead irrigation is not suitable for trees because it will wet the foliage. Opt for drip irrigation.
Keep the Soil Moist
When irrigating, you do not want to flood the drip line. The goal is to keep the uppermost surface moist. The number of gallons to use depends on the soil absorption rate. A soil probe can help you determine the moisture level. However, you should look out for a moisture level at 6 inches below the topsoil.
Tips for Watering New Trees
New trees require more water than established ones. In fact, watering starts right from the transplanting phase to avoid shocking the roots. The root balls must be thoroughly hydrated before covering with soil.
After transplanting, water the plant every day for the first two weeks. After 3 to 13 weeks of planting, reduce the watering to once in three days. Afterward, irrigate once a week until the young roots have anchored to the soil.
To ensure the water gets to the roots, make a reservoir around the earth ball and fill it slowly with water. You can also use a slow-release watering bag or create one with a 5-gallon bucket.
Make small holes under the bucket and then place the bucket around the newly planted tree. Fill the bucket with water. It will penetrate the soil deeply and slowly.
When the bucket is empty, move it about 3 feet away and add more water. Continue doing this until you have watered the circumference of the plant. You can visit https://www.latimes.com/archives/la-xpm-1997-aug-16-hm-22902-story.html to learn more about slow watering.
Plants need water to stay healthy, but the main target should be the roots. If the soil is moist, a little irrigation will do. Deciduous trees conserve moisture during winter. Therefore, irrigation won’t be necessary as there will be less water loss.