Most homeowners need to prune trees, shrubs, bushes, and other plants in their yards on occasion.

Not to be confused with trimming — or the straight cutting back of overgrown plants — pruning is essential to the health, beauty and safety of plants, according to the Garden Editors at Better Homes and Gardens.

Master Gardener Brid Craddock agrees. Pruning, she says, is all about making plants healthier. A landscape designer and owner of Heirloom Gardens, the Newtown resident said that while the practice of snipping away at dead, damaged, diseased or disarrayed branches or stems could appear to be for the purpose of slowing or stopping growth, the practice is in fact the opposite.

“Pruning doesn’t control growth. It promotes growth,” she said. “People think ‘I’m going to make this plant shorter,’ and then next year the plant might grow in crazy new directions. You have to know what you’re doing a little bit. “That’s a hard concept, but whenever you prune, you are redirecting that plant’s energy to promote new growth,” she added.

Regular and corrective pruning keeps trees, shrubs, and woody vines healthy by eliminating some problems and preventing others. Pruning generally encourages new growth, while also controlling a plant’s size. Pruning also helps maintain a plant’s natural form or creates a formal shape.

Removing select branches lets light and air reach more parts of the plant. Branches and stems that are dead, dying, diseased or broken should be pruned.

Right now, Craddock said, is the perfect time to do some pruning. This year especially — with social distancing protocols in place — getting outdoors for fresh air should be a draw for many people.

“It is a perfect time to go outside and prune,” the master gardener recently shared. “You can go outside and there’s no crowding, no crowd will form to help you, I’m pretty sure,” she added with a laugh.

Proper Tools And The Four Ds

Before beginning to work, Brid Craddock says the first thing to do is look beyond the planned work area.

“The thing to look for are overhead wires,” she said. “Use caution with ladders, and pole pruners — pruners on the end of poles, as you might guess.”

The next thing is to have the right tool.

“You want to use bypass pruners,” Craddock said, explaining the hand tool looks “like a scissor. “The other kind of pruner, is a non bypass, and it will say which you’re looking at on the label,” she said. “Bypass are going to be a little more expensive, but they’re worth it. The others crush a stem. Bypass pruners cut cleanly, and reduce the incidence of disease and insect problems.” Craddock works with Felco bypass pruners, which she calls “by far the industry standard.”

Gardeners will also need to choose the right size tool.

“A hand pruner is appropriate for stems of perhaps ¼ of an inch,” she said. “A lopper pruner is appropriate for stems of up to one inch. A toothed saw, or branch saw, is for anything larger.”

Always use clean, sharp tools. Tools should be sharp enough to leave a straight, clean cut. Clean tools between pruning jobs, too. Rub the blades with a disinfectant to prevent the spread of disease.

Then, she said, ongoing priorities of pruning are the same for all plants: looking at the shrub or small tree to be worked on and examine it for the four Ds — dead wood, damaged wood, diseased wood, and disarranged branches. “When left on plants, those parts become a harbor for pests and disease,” Craddock said.

The first three items are easy to spot. The first three on the list are also the first three that should be addressed.

“That’s the order: take out the dead, then the damaged, or anything broken or split; or diseased, which you’ll want to look up,” she said. “Lichens, for instance, are not a disease. It’s a natural occurrence, not a sign of disease. They are a perfectly healthy growth on trees, and even rocks.”

Black knots, however — what Craddock calls “black swellings that look like tar, particularly on cherry or plum trees” — should be addressed. They are caused by a fungus.

In writing for the UConn Home & Garden Extension Center in May 2018 (“Black Knot of Plum & Cherry: Prune Now!”), Joan Allen explained that black knot — or gall — is caused by the fungus Apiosporina morbosa. The abnormal growth, she wrote, “may be overlooked during the growing season when the leaves are hiding the galls, but this time of year they are hard to miss.”

Black knots are “a serious disease of these trees and can eventually kill susceptible varieties,” wrote Allen. “Where manageable, prune out all galls during the dormant season and dispose of them off-site, burn of bury them,” she added, explaining that even removed galls can “still produce spores that can cause new infections.”

One thing that may stymie homeowners is the appearance of sap on trees and plants. That liquid is not always a bad thing.

“If you see oozing of sap,” Craddock said, “that should be examined, perhaps by a landscaper or an arborist, to determine if there is a health issue.” Sometimes, she said, it’s the work of “sap suckers, like woodpeckers,” she continued, “and that does no harm. They peck a hole and they drink the sweet stuff, just like us.”

Once diseased growth is taken care of, Craddock said it’s time to look at disarranged branches.

Disarranged, the master gardener explained, means branches that are crossed, “branches that are growing back into the tree, crossing each other. This is where you need to make the decision of which branch will stay, and will branch will grow. If they are rubbing, and growing back in, one of those branches will have to be removed,” she said.

The best thing to do is stand back away from the plant and look.

“You want all branches to be facing out toward the sun and the light, and crossed branches will be very obvious. There will be many crossed branches if something hasn’t been pruned,” Craddock said.

When pruning, she said, “you can take — and this is true for all plants — up to one third of the height and one-third of the width without hurting the plant. That includes rhododendrons, andromedas, rose shrubs, just about every plant can be removed like that, if your plant is overgrown. It’s okay to remove.”

The basic rule of thumb with pruning is to do less with each cut instead of more. It’s much easier to make another cut than to reattach branches, she pointed out.

Timing

When to prune is also important.

Most pruning, with the exception a few plants that experts suggest waiting until late spring or early summer, “can be done whenever you like,” said Craddock. She offered a few basic guidelines on the few that need to be timed carefully:

Hydrangea: wait until June.

“If hydrangeas are pruned now,” she said, “the flower buds will be cut off. Do not prune in early spring. It’s very tempting because they’re ugly sticks right now.”

Spruce plants: never.

Junipers: Use caution.

In a publication called “The Home Landscape: Pruning,” the UConn Extension Center mirrored Craddock’s thoughts when its authors said in part “Narrow-leaved evergreens, such as false cypress, juniper and arborvitae, may be pruned at almost any season of the year, except possibly when new soft growth is developing during the spring. Some of the narrow, upright junipers seldom required any pruning.”

When it comes to evergreens, the Extension Center’s experts said in part that “much pruning of narrow-leaved evergreens would be unnecessary if more care were used in selecting specimens, with regard to the mature size of the plant and the area involved.”

Maples, birches or boxwoods: Wait until June for all three, she said. On the latter, she said, “They have a common insect infestation, a leaf minor. If pruned in June, the leaf debris will contain the leaf minors, and if removed, you will remove that insect from your property.”

Finally, to preserve the flowering of a plant for the current year, Craddock says homeowners need to wait to prune until after a plant has flowered.

“But do this,” she said, “immediately after the plant has flowered.”

While some tasks are best left to the professionals, pruning is something homeowners can do to maintain and/or improve the health of their outdoor plants, while improving the look of their property.