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Probably the most common question we get is whether a plant can be safely moved from one location in the yard or garden to another and when to move it. This is one area of gardening where a simple and concise answer isn’t always possible, and in fact, is usually unwise. This isn’t a science with a universal set of right answers; experienced gardeners know it’s more of an art, and with inconsistent results at best even if you do everything “right”.
With this in mind, we’ll take a crack at describing for you the preferred process for moving plants, and then you can try your luck from there. Just don’t call us if it doesn’t work out – we warned you that it wasn’t going to be easy!
This info sheet is primarily about when and how to move the plants, not how to care for them once they are in their new location. We’ve written two separate info sheets on that science (or art) which you are strongly encouraged to read in conjunction with this article; click below to view them now;
Dissecting the Move
Let’s begin with the fact that most plants do not like to be moved – ever. There are a number of reasons that plants don’t like to be moved, and they can all be summarized by one principle so obvious it merits restating; plants don’t normally move throughout the natural habitats of their own volition. As a result, they are not designed to move or to be moved, and in fact, they will normally resist being moved. It’s just not in their nature!
Most significantly, plants don’t like to have their roots disturbed. Damaged roots will no longer be able to collect and carry the amount of water that the plant grew accustomed to, which results in an imbalance between the top growth’s demand for water and the roots’ ability to supply that demand.
Actually, it’s the very fine hairs covering the roots which can only be seen under a microscope that extract water from the soil; the roots we humans can see are more like the pipes that carry the collected water to the above-ground parts of the plant. These fine root hairs which collect most of the water are located at the very extremes of the roots.
The root systems of plants can extend as far away from the plant as it is tall (and sometimes much farther). In some cases, these roots may also extend as deep into the ground as the plant is tall or more so that the roots can tap into deep reserves of moisture during periods of drought.
That’s why you may think you’re doing yourself a favor by getting those big, thick roots at the base of the plant, but you’ve only got the main pipes; they may carry the water, but they can’t collect it. You’ll need to get most of those fine roots if you’re going to make the transplant successful, and they can go quite a distance from the plant.
Now it is possible to be extremely diligent in the transplanting process and not damage the feeder roots that we can see, but even a slight shifting of the soil is often enough to damage the root hairs that do the real work. The success of your transplant will be directly related to how few or many of the feeder roots are cut, as well as the extent of the invisible damage caused to the root hairs by digging and moving.
Beyond the Root of the Problem
Besides the roots, there are other factors that can stress a plant during a move. Plants can be sensitive to a changed environment. They may receive more or less sunlight in their new location, or they may be reoriented relative to the patterns of sunlight they grew accustomed to in their original location.
They may get more or less moisture in the new location, and the soil and subsoil may be noticeably different. Each of these is a disruption to the plant that it was not expecting.
Some of the damage incurred in a transplant happens during the move to the new growing location. Branches can be broken, and bark can be nicked or scuffed. Tender, brittle new growth can be easily snapped. If moved in full leaf, leaves can be broken off the plant or torn, and if dormant, buds can be snapped off the branches. All of these will stress the plant and further impact its ability to recover.
With the above in mind, specific types of plants tend to be particularly susceptible to specific problems. Without trying to be all-inclusive, here are some key points to remember when moving different types of plants.
One more thing to note, don’t confuse transplanting plants in your yard with planting potted trees and shrubs that you bought at the local garden center. They may both be going into a new location in your yard, but that’s where the similarities end.
Most garden center stock has been growing in containers for a year or more and was transplanted in a controlled growing environment while dormant.
By this point, they are growing happily in the containers, and any bad transplants have been culled out of the system. You can plant containerized trees and shrubs at any time of the year when the ground isn’t frozen, but you can’t say the same for plants you’re digging out of your garden yourself!
Of all the plants on earth, trees like to be moved the least. They are long-lived and have deep, wide-spreading roots that are almost impossible to keep intact during a move. You can safely say that the larger or older a tree is, the more difficult it will be to move and the less your likelihood of success.
This varies greatly between species; because of their deep taproots, one or two-year-old white or burr oaks may not survive a move no matter how much soil you take with them, while some aggressive trees like poplars and willows can be successfully moved with a spade when they are ten feet tall or more!
The cardinal rule when moving a tree is to move it when it is dormant. This is either the period in late winter before the leaf and/or flower buds have broken, or in fall after the leaves have fallen.
The tree is demanding the least from its roots at this time, and so will experience the least shock when it is moved. This also gives it a chance to spread some new roots before the leaves and flowers place demands on what is sure to be a compromised root system.
It’s a little trickier with evergreens. For one thing, it’s harder to tell when they are dormant because their leaves don’t fall. As well, because they retain their leaves into the fall and winter, a greater demand is placed on the roots throughout the year and they are therefore more susceptible to transplant shock.
Evergreens are best moved in late fall and are usually a challenge to move when they are more than just a couple of feet tall, with few exceptions.
When digging out a tree, dig as wide and deep a soil mass as you can to get as many of the fine roots as possible, and take as much of the soil as you can with the roots. A fair rule of thumb is to take a soil ball the diameter of one-third to one-half the height of the plant, but this is not a hard and fast rule; some need more and some will put up with less than this. Undisturbed soil is best, but this gets exceedingly difficult the larger the plant.
Some trees are resilient enough to tolerate disruption of their root balls and can even be moved bare-root when dormant, i.e. with a minimal root ball and soil.
Many apples and flowering crabs, maples, ashes, locusts, and lindens can be moved when quite large and with less attention paid to keeping the soil intact around the roots. Again, young and dormant are the keys – try this when they are in full leaf and you’re destined for failure.
Once a tree is greater than about 5 or 6 feet tall (with a couple of notable exceptions where taking a whole lot of soil isn’t critical to success) it will become impossible to move by yourself.
Even if you could dig a big enough root mass, you sure as heck wouldn’t be able to move it. At this point, you can hire the services of a professional tree mover. Their digging tools can extract quite a massive root ball around a semi-mature tree, and they have the mobility to get it to its new location without breaking any backs in the process.
There has been much debate as to whether or not to prune the top-growing parts of trees during a move. The hypothesis is that a reduced demand caused by less top growth should balance with the reduced ability of the compromised roots to meet that demand.
The countervailing argument is that trimming off healthy top growth will reduce the plant’s ability to create and store vital energy, thus hurting it even more than the move alone. The jury is generally still out on this one, although the prevailing wisdom is to not intentionally prune any of the top growth.
Much of what was said above for trees applies to shrubs as well. They are best moved when dormant, and evergreen shrubs are much more difficult to move than deciduous shrubs at any time of the year. You want to get as much of the root ball as possible, and some varieties are easier to move than others.
However, in general, shrubs are easier to move than trees. This has to do with their ability to vigorously regenerate from the crown or base, even if the branches and stems are damaged or cut. They also tend to have denser and less wide-spreading root systems than trees, although this varies from species to species.
Shrubs are best moved when dormant, but a few are amenable to moving when in leaf (although they won’t like it), as long as there is no threat of heat stress in the following few weeks. Regardless of species, they should never be moved in the mid-summer heat.
The ability of a shrub to be successfully moved varies greatly between species. Some shrubs tolerate being transplanted particularly well; roses, hydrangeas, dogwoods, and bush cherries can often be transplanted without missing a beat.
As a rough rule, suckering shrubs and those that will tolerate radical rejuvenation pruning (right to the ground) are easier to move under all conditions; sumacs and raspberries can often be moved in full leaf.
On the other hand, shrubs with fine root systems are difficult to move at any time of the year; good luck moving azaleas, rhododendrons, and blueberries!
It is safe to say that almost any perennial can be successfully moved at some point, even when mature. In fact, some perennials have to be moved in order to remain in your garden for any length of time; chrysanthemums must be divided and replanted every few years or they will eventually die out from the center.
The trick is knowing when and how to move perennials because, like shrubs, perennials vary greatly in their responses to being transplanted.
Most perennials can be moved safely when they are dormant. As with trees and shrubs, this is either in late winter before they have resumed their growth (before you see their little heads poking out of the ground), or in late fall after a few heavy touches of frost have stopped their growth. Remember that with perennials, you’re trying to move the crown and roots of the plants, not necessarily the top growth.
The “experts” claim there are some long-lived perennials like baby’s breath, candytuft, and peonies that don’t like to be moved when established, but that simply doesn’t jive with our experience. We haven’t tried growing every perennial on earth, but we have yet to meet one that didn’t tolerate a move when dormant.
Some perennials can even be moved bare-root when dormant. Perennials with bulbs, tubers, or corms are able to store energy in these extremities and don’t require any soil to be transported along with their roots. Examples of these include tulips, daffodils, lilies, irises, hostas, and daylilies.
In some cases, the root parts need to be specially conditioned before they can be stored for transplanting at a later time, but almost all of these will tolerate moves around the garden when the bulbs are dormant. Interestingly, many of these plants will resist being moved when in full growth (particularly the spring bloomers) and should only be moved when the top growth is dormant.
Perennials that move by stolons or rhizomes (underground suckers) are particularly easy to transplant almost any time of the year. These include many of the popular groundcover perennials like vinca (periwinkle), creeping Jenny and thyme. Succulent perennials like trailing sedum and hens and chicks are also ridiculously easy to move; often just a piece of the plant dropped on the ground is enough to get a new plant growing!
As for transplanting in full leaf or full growth, that gets a little more specific. In general, perennials should be moved either well before or well after they bloom; when flowering they are consuming maximum energy. For those being moved after flowering, trim off the seeds as they are forming to encourage the plant to redirect its energy to the transplant. When moving perennials in full leaf, be particularly careful not to break the stems.
There are a few perennials that can be moved when dormant but which have optimal times for moving during the active growing season. Irises can be moved at any time, but are best moved right after blooming; this allows them to develop flowers for the coming season.
Seriously? Let’s just suggest that you try them again next year in a different location!