Transplanting trees and shrubs might seem like an easy task, but the truth is many of them die if the work is done improperly. Exposing roots to the air is a traumatic experience for a plant, and not all specimens survive the ordeal. But if your landscape design calls for moving a tree or shrub to a new location, you'll have a much better chance of success if you learn the proper techniques.
Moving a tree or shrub can be a physically challenging task, so make arrangements to have help on hand if necessary. Also, be aware of any underground utility lines before you start by calling 811, the Call Before You Dig number in the United States.
Equipment / Tools
- Garden shovel
- Tape measure
- Garden hose
Choose a Location
Before transplanting, determine whether the tree or shrub likes sun or shade, as well as what its spacing and watering requirements are. Your new location should meet the needs of the plant as much as possible. For instance, do not locate a plant that craves water next to one that prefers dry conditions. Their needs will be incompatible.
Calculate the Size of the Root Ball
Estimate the width and depth of the root ball (roots plus soil) by doing a bit of exploratory digging around the plant. The width of the new hole should be twice that of the plant's root ball. However, you might want to keep the hole's depth a bit shallower than the root ball to avoid puddling and rotting, especially if your soil has a lot of clay in it.
Dig the New Hole
Dig your new hole before you dig up the tree or shrub. It's important to move the plant to its new home and get its roots covered as soon as possible after you dig it up. The longer the roots remain exposed, the more stress that's put on the plant. When you reach the bottom of the new hole, resist the temptation to break up the soil at the bottom. You might think this will help the plant's roots penetrate deeper, but it actually causes the tree or shrub to sink, inviting rot.
Dig Around the Plant
Begin digging roughly 3 feet out around the perimeter of the tree or shrub. Get a feel for where the central mass of roots lies. The idea is to keep as much of the root ball intact as possible. But with large plants you might find it hard to move the entire root ball because it will be very heavy. It's often OK to cut through some roots on large plants with a sharp shovel or pruners. Be sure to make a clean cut, which helps to prevent disease.
Transfer the Plant to a Tarp
Once you have removed enough soil from around the sides of the plant, you will be able to slip your shovel under it and begin to loosen the plant's grip on the soil below it. After it is loose spread a tarp on the ground nearby, and gently move the plant onto the tarp. With larger specimens, you might need two or three people to help lever the root ball out of the ground.
Move the Plant to Its New Hole
Using the tarp as a sled, drag the plant to the new hole. Gently slide it into the hole, and adjust it so it's upright. The plant should be at the same level (or slightly higher) than it was in its old location. Shovel the excavated soil back into the hole. Firmly tamp down the soil and water as you go to eliminate air pockets, which can cause the plant to shift. Finally, mound the soil in a ring around the plant, forming a small ditch to catch water. This will help keep the roots watered until the plant becomes established.
In the past, the standard advice was to blend peat moss or compost with the soil before filling in around the transplant. Now, many experts believe the fill soil should be identical to the surrounding soil. This will encourage roots to explore outward rather than remaining confined in a small area of unnaturally rich soil.
Care for the Plant
Spread a 3-inch layer of landscape mulch around the transplant. But keep the mulch a few inches away from the base of the tree or shrub to promote air circulation and to discourage rodents from nibbling on the trunk. (Rodents become emboldened by the cover mulch provides.) Then, water well. Frequent watering is essential when transplanting shrubs and trees, especially during the first summer.
When to Transplant Trees and Shrubs
The ideal time to transplant a tree or shrub is somewhat dependent on the species. But for most trees and shrubs, late winter or early spring is the best time for transplanting. Fall is the second best time. However, trees and shrubs with thick, fleshy roots often don't react well to transplanting in the fall. These include magnolias, tulip poplars, oaks, birches, rhododendrons, hemlocks, and flowering dogwoods. These species should be transplanted in the spring instead.
In many climates, frozen ground makes it virtually impossible to move plants in winter. And in summer, transplanting is not advisable because the weather is simply too hot, which puts too much stress on the plant. If transplanting during hot weather, provide shade for the plant for about a week. This will keep the plant from wilting and prevent sun scald to the leaves.
Tips for Transplanting Trees and Shrubs
Root pruning is one technique that is sometimes used to make transplanting large trees or shrubs easier. A tree's root ball is typically around 11 times the diameter of its trunk. This means a trunk that's 3 inches in diameter would have a root ball nearly 3 feet across. It would be no small feat to get that root ball out of the ground.
Root pruning involves severing the outer roots before digging up the plant. Some experts even recommend doing this in the fall prior to spring transplanting. Trench vertically down around the perimeter of the root ball to a depth of at least a foot. The goal is to sever all lateral roots extending out from the tree.
For trees with trunks larger than roughly 3 inches in diameter, consider hiring a tree service to move your plant with a motorized spade. Large trees generally die if you try to dig them up by hand.
Finally, if a tree or shrub must remain out of the ground for more than a few hours before replanting—which might be the case if you're moving it a long distance—swaddle the root ball tightly in burlap. Keep it well watered until it can be planted. Trees and shrubs can remain alive for many weeks in this fashion if the roots stay embedded in soil.