As we approach the zenith of summer in Austin, the data is clear: 27 out of the past 30 days have subjected us to temperatures at or above 100 degrees, with no end in sight and trees need watering. In periods of drought with water restrictions, increased wildfire risk, and no rain in the forecast, what does this mean for our trees? During prolonged periods of drought, trees will make less food and slow their growth.
When a tree is not receiving water from the tree owner or mother nature, the process of photosynthesis slows, and the tree can become stressed. This is an opportunity for diseases and insects to attack. Evaluate your trees to check their health by noticing if they have scorched leaves, wilting, unusual patterns on the foliage, insect holes, frass (insect droppings), or leaf shedding. These can all be signs that your trees need extra care.
Watering trees when we’ve had no rainfall can help get them through our hottest and driest months
But how much to water? Trees generally need 5 gallons of water per inch of diameter. Use less for healthy trees and more for stressed trees and those with roots in turf or ground-cover. Water slowly to ensure adequate soaking; deep, infrequent soaks promote deep roots. If water is running off, cut back the amount you’re watering. After a day, check the moisture level using a screwdriver inserted into the soil to a depth of 4-5″. If dry, water again, if wet, wait until it dries to re-water.
Newly planted trees typically require once-a-week watering, and established trees that appear stressed can be watered as much as needed with monitoring. For newly planted trees, water the root ball thoroughly, for established trees, soak the entire area under the tree’s canopy and beyond, if possible because the feeder roots are in the upper 6″ of the soil. Mulching your tree’s root system can help retain moisture when watering. Spread mulch 3-4″ deep and keep away from the trunk at least 1-2″, depending on the tree size.
Keep in mind that if you are under watering restrictions due to drought, trees will be able to survive (but not thrive) on about half the recommended amount, or 2.5 gallons per inch of diameter. If resources become truly scarce and you must prioritize which trees to save, target those that provide the most value to your property – large shade trees, and desirable species like oaks and pecans.
Have our Certified Arborist on staff inspect your trees for drought stress and make watering recommendations. Call us today at 512-885-TREE, or email us at [email protected]. You can also contact us via our online form.