HEAD: The first cut

DECK: Don't be afraid to prune — with the right knowledge, you'll give shrubs just what they need

 

BY KATHRYN CATES MOORE

Lincoln Journal Star

Pruners give gardeners a sense of empowerment. With one quick cut, you control the destiny of your shrubs.

Sharpened snippers can make the difference between an out-of-control eyesore or colorful curb appeal. Like a bad hair day or good hair day — it depends on where the shears take you.

The trouble is, many homeowners are afraid to make the first cut, said Maggie McVicker, owner of West Fork Nursery with her husband, Mark.

"I'm quite touched by the sentimental feelings of homeowners," she said. "They are so attached to their landscapes. They love their plants and worry about hurting them."

But if they don't prune the greenery themselves, or hire someone to do it for them, ultimately the plants can suffer, she said.

Maybe not the first year. Or even the second. But a shrub or tree left to grow its own way for several years may become a problem.

Gardeners take their pruners in hand for several reasons, said Anne Streich, University of Nebraska-Lincoln horticulture educator. The most obvious is to remove dead, damaged or diseased tissue. Then there is pruning that removes problem branches — the low ones that smack you in the forehead when you walk by a tree or the spirea that scrapes your car as you back out of the driveway.

A more calculated approach is one that will stimulate flower growth or plant shape. This takes some planning and needs to be done at the right time of year to be effective, Streich said. Rejuvenation pruning is just what it sounds like: pruning a plant to bring it back to its former self, but fuller and stronger.

And there are those who prune to create a special form. An extreme version of this might be the Mickey Mouse bushes at Disney World. More commonly, it is the box elder or privet hedge that needs some shearing to stay in shape.

Timing is everything. Pruning shrubs when the mood strikes you is counterproductive.

There are some simple rules.

"If it blooms in early spring, don't prune until after June 1," McVicker said. That includes early flowering shrubs such as forsythia, lilacs and mock orange. You probably won't harm the plant by pruning now, but you will snip off the coming blooms.

Some spirea falls into that category, too. That includes the old-fashioned spirea, commonly called "Bridal Wreath" and "VanHouten." These are the ones with layers of fragrant white flowers that arch toward the ground. They bloom on what horticulturists call "old wood."

Other varieties, such as Japanese spirea and neon spirea (the day-glow yellow-green ones), bloom on "new wood." Those can still be pruned this spring, but not after May 1, McVicker said.

She's often asked, "Won't pruning now delay the blooms?" Yes, she says, it will delay them some, but the plant probably will bloom better and be more full than if it had not been pruned.

The new wood/old wood adage is usually the first pruning rule of horticulturists, but many homeowners are not so technical. Early spring? Mid-summer? Late fall? It can be confusing.

One solution is to chart the pruning times of your landscape or ask nursery experts when you make the plant purchase, then record it.

Another solution comes from a newly published book, "The Pruner's Bible," by Steve Bradley (Rodale, $21.95), which really simplifies pruning. It is a step-by-step approach, with color-keyed drawings and color photos of the plants, so even the least-educated gardener can just look at the pictures and know what to do.

The plant-by-plant portion of the book contains 70 of the most widely grown plants. For instance, under "Rhododendron" there are very specific instructions about how and when to prune them. It also describes the differences between "formative," "remedial" and "routine" pruning on this plant, which tools to use and a tip to prune soon after the plant blooms, so you don't lose next year's flowers.

McVicker said it is always good to consider local conditions and ask if you have a question. Butterfly bushes, for instance, are sensitive to fall pruning; leave it for early spring. Viburnums are better with a summer pruning, but not after Aug. 1, she said.

Tree trimming, where people and chain saws can get into serious trouble, is different than shrub shaping. Overpruning trees can have a serious impact, Streich said.

Here is the downside to over-pruning: It can increase canopy temperatures, making photosynthesis inefficient and it can cause sunscald, decay, sprouts, root decline and even the death of the tree, Streich said.

Most trees planted in our yards have been pruned for form in the nursery. There is a clear stem and a well-balanced framework. Routine pruning might include removing shoots or those thin, whippy branches in the center.

Large branch removal or heavy remedial pruning may best be left to professionals.

If you do trim a large branch, most trees are most adaptable to pruning in the winter, when there is no new growth. A large branch should be removed in stages, taking the outermost sections first, so the branch will not tear away and damage the tree. When you finally remove the final stump, cut it close to the branch's shoulder or collar, cutting first up from the bottom about one-quarter of the way, then from the top. The proper cutting spot is usually easy to see because of the ridge where the branch and trunk meet.

In general, don't remove all of the inner branches and foliage and don't let a secondary branch outgrow the leader. Topping should be avoided at all costs, Streich said.

Evergreen trees present even more difficult issues. Yews are the exception, McVicker said. Yews are the easiest to trim and the fastest to regenerate new growth.

Most conifers (cone-bearing evergreens) go through two growing surges a year. Few can produce new growth on old wood, and some may take several years to recapture their lost growth. Minimal pruning is best for most evergreens, focusing only on damaged, diseased or dead branches.

With yews being the easiest to prune successfully because they have the most buds, McVicker said, junipers are the next easiest. She believes pines are the most difficult and spruces the second most difficult to prune.

Reach Kathryn Cates Moore at 473-7214 or kmoore@journalstar.com.