Ideal Tree Spacing & Pruning Tips

Winkel KM 02By Nick Sargent

There are two issues that I often see effecting the long term value of trees.  The first is that trees are often planted too close to buildings, homes or other plants. This is true of shade, ornamental and evergreen trees.

I realize that when planting a tree ten or twenty years seems a long way off and not of much concern. However, the future comes quickly and it is a disappointment when a tree finally reaches its mature size only to be compromised by its proximity to either a building or another tree. Although there are exceptions, a good general rule is to take the full width of the variety at maturity, divide it in half (since the trunk is in the middle of tree so half of width will go toward the building and half away), then not plant any closer to a building than this. In cases of planting trees near each other, do the same equation for each tree, then add the two results together. This will ensure that at maturity the trees are not close enough to damage each other.

The second issue I often see is trees that are not pruned properly when young so trees have low branch crotches and a poor shape. Low branch crotches become weak with time as mass increases farther up the tree. Picture these angles as the letter “Y” with the lower part being the trunk. Then imagine the crotch beginning low on a tree early in its life. As mass grows above the split, major force is put on this crotch.  It is also a rule that the tighter the crotch angle the weaker it is.  Most tree varieties will do best in the long run with any potential split leaders being pruned off until the tree reaches fifteen to twenty feet in height. To do this you must pick one part of the “Y” and prune it off leaving only one to become the sole leader.  This is sometimes difficult as it removes a significant portion of the tree canopy, however, trees recover from this amazingly quickly.  Low branches should also be pruned as a tree grows to allow a person to comfortably walk underneath and sometimes higher. This trimming will also reduce wind load on the tree as the surface area is reduced. In both cases, pruning for a proper leader and lower branch height will lead to the best visual appearance, plus promotes the best long term health. Stop at either Sargent’s location for advice on these or any other tree concerns.

Maackia amurensis

Written by

"Jill" of all trades at Sargent's, Nina Sargent co-owns Sargent's with her husband and in-laws. She keeps communication going between the garden centers, landscape, nursery and the public. Nina loves helping connect people with their outdoor living spaces - especially while creating habitat for wildlife. She enjoys running, skiing (of all kinds) and reading.