Extreme heat and drought can take its toll on trees and shrubs. Adequate watering is essential for the survival of even well-established trees.
Step 1: Watering in the morning is recommended, but during times of extreme heat, watering at night reduces surface evaporation and allows for maximum water absorption. Setting a system up with water timers and soaker hoses is a great way to create an easy and efficient watering routine.
Step 2: Large woody plants and well-established trees should be watered every one to two weeks with approximately 10 gallons of water per inch of trunk diameter. Small woody plants and young trees typically need to be watered once every three to four days. Watch for signs of stress such as leaves that are wilting, curling, browning, or falling off the tree. Established plants can take up to two years to show signs of stress, so do not assume if a tree looks healthy it is doing well.
Step 3: The roots responsible for soaking up water tend to concentrate around the outer perimeter of the plant in an area referred to as “the drip line.” The drip line forms around the plant and extends slightly out past the tips of the branches to encompass the area where water drips during and after a rain. Watering along the drip line is the most effective method for ensuring proper water absorption.
Step 4: Sprinklers work fine, soaker hoses work better. For single plantings and established trees, nothing beats a root feeder. Root feeders (used without fertilizer) water below the ground surface, increasing soil aeration and virtually eliminating loss to evaporation.
Step 5: Typical sprinklers deliver about 4 gallons per minute. Soaker hoses and root feeders deliver about 2 gallons per minute. For root feeding, calculate the amount of water each tree needs and divide it by the number of spots along the drip line you plan to water at.
Smaller trees should be watered at four spots long the drip line, while larger trees may require as many as six to eight feeding spots. Drive the root feeding stake 12 inches to 14 inches into the ground along the tree or shrub drip line.
Allow the water to flow for the calculated amount of time and then move the root feeder to another spot along the drip line. Continue the process until the appropriate amount of water has been applied.