The primary concern for new trees is adequate access to water. There is no one-size-fits-all approach to watering. Keep the soil and mulch moist, but not soggy. If there is standing water around the base of the tree, it has been overwatered. Overwatering saturates soil and deprives the roots of oxygen; if the condition persists it can kill the tree.
The boulevard trees planted by the City are known as containerized trees as they come from nurseries in plastic pots. These young containerized trees lose most of the water their root ball was holding to the surrounding soil during the planting process. While location, weather, and soil conditions should always be considered, containerized trees – both deciduous and evergreen – require frequent watering after planting. Having adequate water early in the growing season is essential for root expansion as they actively seek out and grow into moist soil, increasing their anchorage and providing important nutrients for growth.
New trees benefit from frequent watering. Your boulevard tree may have a slow-release watering bag attached. You can help by filling the bag on days when it is empty. Trees benefit from a gallon of water per day for the first two weeks. After two weeks, they should be watered every other day. After two months, it only needs to be watered once each week until the ground freezes. An inch of rain counts as a watering.
During hot/dry summers newly planted trees and those put to ground within the last five years need more frequent watering, every three to five days.
Do not apply lawn chemicals of any kind on the boulevard strip where trees are planted.
Weed-whip trimmers harm trees; keep them away from trees.
The most sensitive part of a tree is its root system. Keep roots moist during the summer, and protected from cold Minnesota winters, by covering them with 3-4 inches of mulch. Keep the mulch away from the trunk of the tree.