Q: I planted a blue holly about three years ago but now realize that it is too big for the area. I don't want to spend the rest of my life butchering this plant to keep it in bounds and would prefer to move it. How do I go about it, and when is the best time to move it?

A: It can be tricky to move a plant once it has become established in a site, but it is possible. Take a minute to evaluate the new site to be certain that it meets the holly's cultural preferences: full sun to partial shade; evenly moist, well-drained, slightly acid soil; and an eastern exposure to avoid winter leaf burn and summer heat stress. And make sure there is adequate room for the holly's growth. Depending on the cultivar, blue hollies (Ilex x meserveae) grow about 8 feet tall with a similar spread.

Moving established plants is risky because you lose the majority of the fine feeder roots responsible for absorbing water and nutrients from the soil. Root pruning is a way to encourage the plant to grow new feeder roots in the future root ball prior to the move. This helps reduce transplant shock and increases the likelihood of moving the holly successfully. Plan to dig the largest root ball you can manage, at least 6 inches of root ball per foot of spread of the holly. The minimum recommended root ball for such a plant is 16 inches in diameter, but the bigger you make it, the more feeder roots you preserve, and the more likely it is that your holly will re-establish happily in the new site.

Root pruning is best done in early fall, then move the holly the following spring. Broad-leaved evergreens such as hollies are best planted -- and transplanted -- in spring. Unless there is another urgent reason for moving it this spring, wait until next spring so you can root prune it properly.

There are different methods for root pruning. The simplest, spading, means simply pushing a spade into the soil all around the circumference of the holly, making sure to create a large enough root ball. Push the spade in 12-15 inches deep. Spading is sufficient for small plants and ones that have not been growing in a site too long, like your holly.

Trenching is a more involved method and is usually reserved for larger trees and shrubs or those that have been established in a spot longer. Create an 8- to 12-inch-wide, 12-inch-deep trench around the circumference of the shrub. The outer edge of the trench will become the outer edge of the root ball. Backfill the trench with a soil mixture of two parts good topsoil to one part compost. The idea is that feeder roots will fill the trench by the time you transplant the holly.

Whichever method you use, prune the roots and leave the holly in place until spring 2009. Be sure to provide supplemental water when we have dry weather between root pruning and digging. A 2- or 3-inch layer of mulch will help conserve soil moisture and moderate soil temperatures and create a favorable environment for new feeder roots to grow. Avoid allowing the mulch to touch the stems or trunk of the plant.

In early spring 2009, dig the new hole so that it is no deeper than the holly is growing in its current site. Make the hole at least twice the diameter of the holly's root ball. Water the root ball thoroughly before you move the holly to help it remain intact while you dig. Carefully dig the root ball out of its site. You can wrap it in natural burlap, securing it around the stems or trunk with twine to help hold the root ball together until you get it to the new site. Remember that even though a good-sized root ball is heavy, it is also very delicate. Handle it like a newborn baby! Always handle balled and burlapped plants by the root ball, never the trunk or stems. There is a strong possibility that the plant will die if its root ball is broken.

It will help to use a wheelbarrow or garden cart to get the holly from the original site to the new site. Settle it into the new planting hole and make sure it is no deeper than it was growing before. Do not use any kind of fertilizer in the planting hole because it can burn tender new roots that should begin to grow quickly once the holly has been replanted. Backfill with the soil you removed to dig the new planting hole.

Water it thoroughly and mulch with 2 or 3 inches of mulch, but do not leave any mulch touching the stems. Pay careful attention to watering throughout 2009. Check for soil moisture by sticking your hand under the mulch and feeling the soil. If the soil is dry 2 or 3 inches below the surface, give it a good soaking. If not, wait a few days and check it again. Although you never want the newly transplanted holly to dry out completely, you also do not want to kill it with kindness by watering too much.