Archive for Thursday, February 7, 2013

Garden Calendar: Taming overgrown shrubs

February 7, 2013


This honeysuckle was dying for a good renewal pruning.

This honeysuckle was dying for a good renewal pruning.

Rejuvenation pruning took the honeysuckle back to short stubs, from which new shoots will grow this spring.

Rejuvenation pruning took the honeysuckle back to short stubs, from which new shoots will grow this spring.

The beast of a honeysuckle at the back corner of my office building has been crying for a good rejuvenation pruning, and the time has finally come. Honeysuckle is one type of plant that can tolerate and benefit from rejuvenation or renewal pruning, a method of pruning that is best performed in early spring before new growth begins.

This particular honeysuckle anchored the corner of the building for years and minded its own business. When another building went in nearby, the space between the two buildings was fitting for a courtyard garden and outdoor classroom. The honeysuckle was the only thing blocking the path ­— literally.

Rejuvenation pruning will take the plant back to short stubs, from which new shoots will grow this spring. The honeysuckle can be shaped and kept in check with moderate summer pruning in the future. Although this might sound like a lot of work, the other option is removing it, grinding the stump, and purchasing a new plant that has a smaller mature size. Because this plant is established and should tolerate being kept a little smaller, leaving it seemed like a better option.

To get the honeysuckle down to size, I will use loppers, pruners and a handsaw. Loppers and pruners with curved blades, also called bypass blades, are my weapons of choice because the curved blades cause less damage to remaining plant tissue than straight blades. I also prefer a curved blade handsaw that cuts on the backstroke.

Kansas State University’s “Pruning Shrubs” guide says multiple-stemmed shrubs like this honeysuckle can be pruned to six-inch stubs. A single-stemmed shrub like a burning bush should be left taller, with heading cuts made back to visible buds.

Overgrown lilacs, forsythia, barberry, spirea, viburnums, weigela and yews are typically good candidates for rejuvenation pruning. Crape myrtles, butterfly bushes and hydrangeas may also benefit from rejuvenation pruning in years when the plants freeze back to the ground or suffer extreme winter injury. Junipers and pines are intolerant of heavy pruning like this and will have to be removed and replaced if they outgrow their space. For other species, check with an expert before taking a chance.

For smaller, better-behaving shrubs, prune as lightly as necessary to shape the plant and encourage new growth. This can be done from early spring to late summer, with care given to the plant’s bloom time. Early spring blooming plants such as lilac and forsythia are best pruned after they bloom; summer blooming plants are best pruned in early spring. Another thing to keep in mind about rejuvenation pruning is that the plant’s blooms may be lost for the year.

To thin and shape shrubs for regular maintenance pruning, always prune back to another bud or branch. Make cuts at about a 45-degree angle on the stem and just far enough away from the bud to avoid damaging it. Stubs that are left too long will die back to the bud.

A note about honeysuckle: There are about 180 species worldwide. The honeysuckle at my office, Lonicera fragrantissima, is adaptable to many soils and site conditions and is well-suited to northeast Kansas without being problematic.

Some honeysuckles are known to choke out existing native vegetation and are considered invasive in some states, although they are yet to be designated as such in Kansas. Amur honeysuckle (Lonicera maackii) and Morrow honeysuckle (Lonicera morrowii) are the two biggest offenders and are referred to collectively as bush honeysuckle.

If you have bush honeysuckle or know where it is growing, removal or control is the best option.

— Jennifer Smith is the Horticulture Extension Agent for K-State Research and Extension in Douglas County. She can be reached at 843-7058.


Ron Holzwarth 5 years ago

In 1990, I moved into a very old home home in St. Francis, Kansas that had been built in 1925. It was one of the 'kit homes' that were very popular during that era. It had two very large yews planted in front of it, right in front of the house. There had been no yard maintenance or cleaning done in many years and the yews were about 15 years old, I was told by the neighbors. They were very large. I was very surprised to trim and clean underneath one of them a bit, and discover a sidewalk underneath it that led to the driveway.

They were both so huge that something had to be done, in the sense of topiary. After thinking about at the possibilities for a few days, I decided that very large rectangular cubes were the answer, with a curved cutout on the corner of one to accommodate the curve in the newly discovered sidewalk.

The yews ended up to be rectangular cubes that were about 7 feet long, 4 feet deep, and one was about 5 feet tall, and the one with the curved cutout was about 4 1/2 feet tall. Something like that, I don't remember exactly.

They were a bit spotty for the first couple years, but then they filled in very nicely, and were admired by many people who had no idea such a thing was even possible.

But there's a problem with doing something like that. Topiary requires endless maintenance. The next purchaser of the home maintained the rectangular yews, except he leveled the tops, that is, he made the tops to be equal heights. I thought that ruined the Art Deco look.

And the owner after that didn't want to maintain them at all, or didn't like yews. Either way, he removed them completely. At least I have a picture of them from when they still looked good.

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