Tree Trimming Time is Now

As much of North Dakota just received some much needed moisture in the form of snow, most of us are not thinking much about spring landscaping and maintenance. Every year I receive calls in May or June asking when they should trim their trees and shrubs. Well for most woody plants, that time of year isn’t suggested. March is a great time to trim deciduous and coniferous species as they are still dormant, which will minimize sap flow. Do note that if you are going to trim maple or birches, they have a heavy sap flow, so those could be trimmed after full leafing out.

Most shrubs will only bloom on last years growth; lilacs and spirea for example, those should be rimmed after they are done blooming. Trimming most shrubs too early can remove the buds and chances for flowers. Of course, if a branch is having a safety concern for yourself or others, you can ignore the seasonal recommendations and trim those when needed.

Whether you are pruning to keep shape, remove diseases or to keep out of the way of electrical poles, all woody plant species will need a trim throughout their lifetime. If you are removing a branch because of a diseases, example black knot, remove 10 inches below the seen symptom or canker. When trimming out diseases it is important to disinfect your trimmer between trimming each branch. If you don’t disinfect with a bleach solution, you might just be spreading the disease to other branches or trees. Simply using warm water and 10-20% bleach will be sufficient.

When you are trimming for maintenance, doing so yearly will keep the canopy open and help prevent diseases. Pruning yearly for fruit trees is suggested as it will increase air circulation and sunlight which can help give you a higher yielding crop. For more information, please call the extension office to receive a copy of the NDSU Extension Service publication Basic Guidelines for Pruning Trees and Shrubs.