When planted in the spring, trees must split their energy reserves between growing roots and putting out leaves. It’s also a race against time because they must be ready to deal with rapidly rising temperatures, high water loss due to evapotranspiration (water evaporation off leaves into the atmosphere) and, more recently, the extended drought that follows in summer months! Spring is a great time to plant, but as they enter the hot season trees need a bit more of a helping hand (extra watering, etc.) from their homeowner to get them established.
As the summer winds down and the air temperature begins to cool, the soil remains warm for a much longer period. It’s similar to lakes, where the water can actually feel warmer than the air in early fall. Trees benefit from the warm soil as the air temperature drops, as it reduces water loss and helps with transplant shock. With no leaves to maintain as they move into their dormant period, trees can focus all of their energy on growing roots and preparing for the winter ahead.
In spite of all this, it is important to note that trees planted in the fall may have different requirements. Mulch becomes even more important at this time of year. It acts as an insulator and prevents rapid freezing or thawing of the ground, which could cause heaving and disrupt how the tree was planted. The tree also needs regular watering until the ground freezes. But overwatering can cause ice crystals around the roots and prevent water uptake, so remember to check underneath the mulch to see if the ground is dry or frozen before you water!
Why not take advantage of the cooler weather and get yourself a tree today?
LEAF offers a subsidized Backyard Tree Planting Program for private property. The program is supported by The Town of Newmarket, The Regional Municipality of York, City of Toronto, Toronto Hydro, Oakvillegreen, Town of Ajax, and Ontario Power Generation. For details on how you can participate, visit www.yourleaf.org.