May is Arbor Month in Minnesota but not only that, May is the season of plant sales offering trees and shrubs and spring temps along with rain (hopefully) therefore, May is an excellent time to plant trees. If you were lucky enough to receive and plant a new tree or shrub and do want the plant to live for more than one season, remember to offer water on a semi-regular basis. DO NOT simply rely on rains throughout the growing season. Read Wise watering practices for newly planted trees and shrubs for a detailed description of watering newly planted trees and shrubs in Minnesota.