Moving Mature Trees: When And How To Transplant A Large Tree

mature tree
mature tree
(Image credit: InaBella)

Sometimes you have to think about moving mature trees if they are inappropriately planted. Moving full-grown trees allows you to change your landscape dramatically and relatively quickly. Read on for information about how to transplant a big tree.

Moving Mature Trees

Transplanting a big tree from the field to the garden provides immediate shade, a visual focal point, and vertical interest. Although the effect is much quicker than waiting for a seedling to grow, a transplant doesn’t happen overnight, so plan far in advance when you are transplanting a big tree. Transplanting an established tree takes effort on your part and causes the tree some stress. However, moving mature trees doesn’t have to be a nightmare for either you or the tree. Generally, a big tree loses a significant portion of its roots in a transplant. This makes it hard for the tree to bounce back once it is replanted in a new location. The key to successfully transplanting a big tree is to help the tree grow roots that can travel with it to its new location.

When to Move Big Trees

If you are wondering when to move big trees, read on. You can transplant mature trees either in fall or in late winter/early spring. The tree transplant has the best chance of success if you act during these periods. Only transplant mature trees after the leaves fall in autumn or before bud break in spring.

How to Transplant a Large Tree

Learn how to transplant a large tree before you start digging. The first step is root pruning. This procedure involves trimming the roots of the tree six months before the transplant. Root pruning encourages new roots to appear close to the tree, within the area of root ball that will travel with the tree. If you will be transplanting a big tree in October, root prune in March. If you are moving mature trees in March, root prune in October. Never root prune a deciduous tree unless it has lost its leaves in dormancy.

How to Root Prune

First, figure out the size of the root ball by looking at the charts prepared by the American Association of Nurserymen or talking to an arborist. Then, dig a trench around the tree in a circle that is the appropriate size for the tree’s root ball. Tie up the lowest branches of the tree to protect them. Cut the roots below the trench by inserting a sharp-edged spade into the earth repeatedly until the roots beneath the circle of the trench have all been cut. Replace the earth in the trench and water the area when you are done. Untie the branches.

Transplanting a Big Tree

Six months after root pruning, return to the tree and tie up the branches again. Dig a trench about a foot (31 cm.) outside the root pruning trench in order to capture the new roots that formed after pruning. Dig down until you can undercut the soil ball at an angle of about 45 degrees. Wrap the soil ball in burlap and move it to the new planting location. If it is too heavy, hire professional help to move it. Remove the burlap and place in the new planting hole. This should be the same depth as the root ball and 50 to 100 percent wider. Backfill with soil and water thoroughly.

Teo Spengler

Teo Spengler has been gardening for 30 years. She is a docent at the San Francisco Botanical Garden. Her passion is trees, 250 of which she has planted on her land in France.