Proper Irrigation – This is the most important factor in establishing your new trees.
How much is needed – New plantings need to receive the equivalent of 1″ of slow steady rainfall each week during the growing season (April – November/December).
Large caliper shade trees and evergreens are best watered with the hose set at a slow trickle at the base of the tree for 45 to 90 minutes. If the trees are also being covered by lawn sprinklers, the watering times need to be adjusted. The goal is to give the tree a deep soaking.
Water with a hose set at a slow to medium trickle and let it run 1 to 2 minutes for each shrub. Best penetration is accomplished by watering one plant for 30 seconds, then another plant for 30 seconds, then back to the first plant. Soaker hoses also provide a good deep soaking and are useful when watering large groups of shrubs.
Too much water can kill plantings just as quickly as not enough water. If your new tree is planted in a lawn also watered with lawn sprinklers or irrigation systems, the soil inside the mulched berm needs to be checked before watering to see if water is needed. Irrigation systems may need to be adjusted to decrease their frequency and/or timing of the soil inside the tree berm seems to constantly be wet. Check by probing the soil with a long narrow instrument. If it penetrates easily into the soil surrounding the rootball, the ground is moist. If the instrument comes out of the ground with water on it, too much water is present and watering needs to be reduced.
The trees often will be fertilized upon installation with a timed release fertilizer. No further fertilization needs to be applied the first growing season. Care needs to be taken to avoid over-fertilization. The first year following planting the tree needs to establish a well developed root system and avoid making excessive foliage growth.
Trees and shrubs can be lightly pruned to shape at any time of the year. Extensive pruning of established plantings should be done in the winter or early spring.