Trees are often ignored when it comes to watering, perhaps because it is assumed that they get sufficient moisture from the lawn or from deep in the soil. While this is sometimes true, at other times trees may suffer due to drought stress, even if the lawn nearby is green and lush. The following guide can help you better manage irrigation for your landscape trees.
Drought Stress Signs
Know the signs of drought stress so you can recognize and correct this problem before permanent damage occurs. The leaves on a tree suffering from drought may start to turn yellow, or they may actually brown and dry out, typically around the leaf margins first and then spreading to the whole leaf surface. Surface roots may also push up in the soil, so you may notice more roots at ground level around the tree and lawn.
Deep but infrequent watering helps ensure that a tree roots deeply and produces a good network of roots to support the tree. Lawn irrigation is only shallow watering, which is why it isn't sufficient for trees when the weather is dry. Trees need about 10 gallons of water per inch of trunk diameter, applied every couple of weeks. Simply pour the water around the trunk and let it soak into the soil.
Newly Planted Trees
Trees that have been planted in the last year or two require more frequent irrigation. One way to ensure that they get enough water is to build up a ring of soil, about 6 inches tall, around the trunk. Make the inside of the ring about 3 to 4 feet across. Then fill the ring with water and allow the moisture to slowly seep into the root zone. Use this method once weekly during droughts or extended dry periods, and every two weeks otherwise.
Mulch can also help with moisture management for your landscape trees. Mulch suppresses weeds, which means your tree has less competition for water. Mulch also helps prevent rapid evaporation so your tree won't suffer from as much moisture loss from the soil. When using mulch, spread it to a depth of about 3 inches, and cover the root zone of the tree. Just make sure the mulch isn't pushed against the trunk, since the trapped moisture could cause the bark to rot.
For more help, contact a residential tree care service in your area