I recently fielded a query about moving a shrub: Was this a good time to do so, or would the spring be better? I responded that either was all right, but that spring might be better. There is no clear answer among experts, some favoring spring, some fall.

I know from my readings that scientists have determined trees and shrubs use photosynthesis to create and store excess carbohydrates in their roots during the summer, and then use them to extend their roots in the fall. They do this even after leaf drop, only stopping when the ground freezes. This would lend credence to those who say, “Plant trees in the fall.”

On the other hand, it is already late October, so plants moved now have less time to get established than those moved or planted in the spring. I wouldn’t want my shrub to get pushed up by freezing and thawing of the soil. The downside to planting in the spring is this: most of us are not like- ly to remember to water a new planting every week, and dry times can damage plants that have not settled in.

Despite all that, I recently moved a shrub that had gotten too big and was crowding a rhododendron next to it. The shrub, a pink spirea, had been in the ground about a decade, and was now about 5 feet tall and wide.

My favorite tool for digging up large plants is a drain spade. This is a shovel with a long, narrow blade — the business end is 16 inches long and just 5 or 6 inches wide. It allows me to get under the shrub, severing roots and giving me leverage to pry it out of the ground.

Most shrubs have roots that are in the top 6 to 12 inches of soil, and this spirea, a tough and tenacious plant, had roots down a full 12 inches, perhaps more. I pushed the blade of the spade in under the shrub at a 45 degree angle, doing this repeatedly as I moved around the plant. I was able to get my spade under the center of the shrub, and each time I tipped the spade back, lifting the root ball a little. Eventually I was able to tip the spirea over onto its side and roll it out of the hole.

I measured the root ball so that I could dig an appropriate sized hole in the new location. The root ball was 12 inches from top to bottom and about 2 feet from side to side — and weighed at least 50 pounds, I would estimate.

Whether planting a new tree or shrub or moving one, it is important to dig a hole just the depth of the root ball, not deeper. The new hole should be about three times the width of it. The reason for a wide hole is to allow roots to spread more easily and get well established more quickly. In my case, I did not dig a 6-foot wide hole as the soil was not compacted, but loose and fluffy.

If I had been planting the spirea on a lawn with compacted soil, I would have loosened the soil in a wider zone. Even so, my hole was 4 feet wide or twice the width of the root ball. I dug a hole with a flat spot 12 inches deep for the roots and with sloping sides.

It is also important to plant a tree or shrub with the same compass orientation that it had before you bought it. For purchased trees, look for the least leafy side — that is generally the north side. The trunk of the north side, if planted facing south, can be sunburned or scalded by the winter sun. That is less a problem for multi-stemmed shrubs.

I don’t recommend giving fertilizers to trees and shrubs. I don’t want to force any fast growth, particularly now, nearing winter, and even a slow-release organic fertilizer will contain nitrogen (which pushes green growth). I do give my trees some rock powder — Azomite is a brand-name of a bagged mineral powder I use. It contains many micronutrients that may not be in my soil, but no nitrogen. I added Azomite and some ground granite dust to the soil before I planted the spirea.

The final touches to this job were to water it well, helping it to settle in and getting rid of air pockets which can damage roots. Lastly, I spread a 3-inch deep layer of all-natural ground hemlock bark around the shrub. This will keep the soil warm longer, allowing my shrub to keep extending its roots. And I’ll try to remember to water it next summer if we have dry times.

HENRY is the author of four gardening books. You may email him at henry.homeyer@comcast.net or write him at P.O. Box 364, Cornish Flat, NH 03746. See Henry’s regular blog posts at https://dailyuv.com/gardeningguy.