Root Pruning
Written by: Dottie Baltz
Root pruning is the act of cutting the roots of a tree or shrub around the drip line to encourage feeder roots to grow inside the drip line to make it easier to transplant. This is usually done on established trees and shrubs that have been in the ground more than a couple of years. Root pruning dramatically increases the survival rate of these trees and shrubs that have to be moved.
It's really important to plant trees in shrubs in the proper location from the beginning, but things happen, and sometimes you just have to move them. If you need help with that, check out my article on moving trees and shrubs here.
Ideally, root pruning should be done a year prior to the move, but it has also been successful with only a 2-3 month lead-time. Generally, I plan my garden changes a season ahead, so in the spring I might root prune something that I will be moving in the fall or vice versa.
To start your root pruning project, simply take a shovel with a straight blade and stick it straight down into the soil at the drip line. Go all around the tree or shrub in a circle, severing the roots as you go.
To determine where the drip line of the tree or shrub is, look at the foliage on the plant and determine how wide the canopy is, then go straight down. That is where the drip line is. It's hard for a plant to get water and nutrients under the leaves, so the feeder roots grow out beyond the leaf canopy. When you sever all those roots, the plant will grow new feeder roots within that hole, closer to the trunk. These new roots are essential for survival after the plant is moved.
Root pruning is also done to stimulate fruit trees to bloom and to keep certain trees a smaller size. It can also encourage stubborn vines to bloom.
So remember, with a little planning, you can successfully transplant a small tree or shrub by root pruning first. Happy Transplanting!