Written by Lynne Jaques and published on https://gardenerspath.com/
A well-maintained tree or shrub is healthier and looks better — two very good reasons to learn how to prune correctly. Proper tree-pruning and shrub-pruning help.
Pruning trees and shrubs is perhaps the least understood and most abused of all gardening chores. Many people prune their plants for the same reason some climb mountains…because they’re there. They head outdoors with loppers and a saw in hand with little knowledge of the plant’s ideal form, the best time to prune, the proper way to make a pruning cut…or when to stop. Incorrect pruning results in poor growth, unnatural plant forms, and poor flower and fruit production.
PRUNING ORNAMENTAL TREES AND SHRUBS
It was brought home to me one afternoon as I looked out my bedroom window to see if I could find any flower buds on my Magnolia campbellii that bloomed so heavily last year. I saw no newer buds but I did notice some of my other plants were taking up much more space than they should and some were getting shaggy. Pruning ornamental shrubs and trees calls for all of the same tools that are used for roses and fruit trees, plus a good pair of hedge shears.
Cuts on ornamentals may need to be coated with a tree seal just as those on roses and fruit trees do. On checking my tree seal I found it a bit thick for good spreading so using a strong wooden, ladle I added water, beating in a little at a time, until the black mixture was the consistency of honey. Then it could be painted on the wound with a brush without running down the branch.
My first task was the pruning of the Osmanthus fragrans, or sweet olive, just outside the bedroom window. It had been passed over the last two years and was getting quite shaggy. My plant is approximately 10 feet high and I usually keep it about three feet wide. Now, a foot must be removed from each side and the front. Using the hedge shears I started at the bottom and clipped the sides until they were even and fitted into the wall space they were supposed to cover.
The top had to be cut back with toppers as the upward growing branches were too large for the clippers. To keep this plant under control, the correct way I should have spent some of my summer pinching out the stem ends to make the growth more compact.
My Arbutus uneda, aka strawberry tree, is planted at the corner of my drive so neither I nor my neighbor can see to enter the street safely when it gets too large. Paint the wounds to control disease germs floating in the air. On this shrub I use the loppers and remove one branch at a time, shaping, training and thinning as I work. This plant has a beautiful stem pattern and it is a shame to hide this beauty.
Trained as a multiple trunk small tree this plant is outstanding. Dead branches should be cut out as soon as they are noticed. Arbutus menzleli, or madrone, should also be trimmed now but prune only to keep the head symmetrical.
My Choisya ternata has gotten completely out of hand as we planted a Japanese maple near by and it has caused the Choisya to reach but for more light. This evergreen shrub that perfumes the air so wonderfully in spring can be pruned very hard and it will come back beautifully. The best time to prune, this shrub is immediately after it flowers.
Start by thinning out the older branches in the center to encourage new growths. When-this is done shorten the remaining branches, making the cut just above an eye to bring it down to the height desired. It will be bare for a time but it is a fast grower. Almost before you realize it the ends will be covered with leaf fans. While there is space to work it is a good idea, to loosen the soil a bit, give the plant a liberal dressing of fertilizer and water it in. If the tips are pinched during the growing season to keep the plant shapely, heavy pruning will not be needed.
I also grow a number of clematis. Because of my love of color I have chosen the types that bloom in both spring and summer. I cut the vines back to within two feet of the ground when I want to keep a plant just fence high (about five feet) but in one area we wish it to climb over to a second fence about four feet away. In this instance I train a couple of leaders on plastic-coated wire as far as they will go and cut back any other branches.
The laterals on the two leaders are cut back to two nodes or joints. Clematis armandii is a so-called evergreen and in many instances it keeps its leaves the year around but in some exposures it will drop a good half of its foliage. This clematis should be pruned every year immediately after it has flowered. If it is not-pruned annually dead wood will pile up in the center of the plant and make an excellent home for garden pests.
Pruning Other Ornamental Trees and Shrubs
One prized shrubs is Sarcococca ruscifolia (I know of no common name), a most delightful, easy-care evergreen that opens its fragrant little blossoms. This shrub is a somewhat slow and orderly grower that stays quite neat and compact. However, if you planted it too close to a walk, as I did, you may have to prune it back. You can cut offending branches to soil level and the roots will send up new shoots that will stay, out of the way for two or three years.
My two dogwood trees are my pride and joy. Both are Cornus florida, (one white flowered, one pink). As these trees have flower buds on the tips of each branch I wait until after flowering to do any little pruning that is required. This consists of shortening – any wayward branches and cutting out damaged and weak branches. These trees are members of that small group of easy-care-plants and should be much more widely grown. Just be sure to pick the right spot when you plant as they resent having their roots disturbed once they are established in the garden.
I grow a French pussy willow (Salix caprea) just for its branches as I enjoy using them in arrangements. All of the willows have very invasive roots so place one of these trees as far away from sewers and drains as possible. Also make a habit of root pruning the plants at least every two years to keep them controlled. I also cut the top back nearly every year to keep the plant at a reasonable height and to get straight, supple branches that are easily bent and shaped.
Original post here https://gardenerspath.com/how-to/pruning/ornamental-trees-and-shrubs/.