Pruning Tips to keep Plants Healthy
One of the most important aspects of landscape management is proper pruning. Not only does correct pruning help keep a garden looking beautiful, it also maintains the health of the plants, saving homeowners time and money. The timing of pruning and pruning technique differs depending upon the type of plant being pruned. Trees, shrubs, perennials and vines can all be pruned. Some are pruned in the winter, others in the spring after flowering. Here are the basics you need to know to properly prune your plants.
Necessary Pruning Equipment
There are a few staple pruning tools that every gardener should have in the garage.
• Pruning saw
These are saws that generally fold in half, with the blade resting in a groove in the handle. Branches up to five inches in diameter, or so, can be pruned with these, depending upon the size of the blade.
• Bypass hand pruners
The two most famous makers of these tools are Corona and Felco. The bypass pruner is more desirable than anvil pruners, in the hand pruner size, because it produces a cleaner cut. Standard bypass pruners can cut branches up to an inch in diameter.
• Bypass loppers
These have the same blades that bypass pruners have, but the handles are between 12 and 24 inches long, and the blades are larger. These can cut branches up to 2 ½ inches in size.
• A step-ladder
You should never hold your pruning tools higher than eye-level. A step ladder can help you reach higher branches; however, any branches that are very high up and large will most likely need to be removed by a professional tree-trimming service.
With those four tools, a homeowner can take care of most of the pruning tasks needed on a regular basis.
Pruning Myths, Busted
Before detailing proper pruning techniques, there are few myths about pruning that need to be dispelled.
Myth: You should always seal pruning cuts with something.
Fact: You should NEVER seal pruning cuts with ANYTHING. Not small cuts, not large cuts, not even if you remove half of a tree. If you prune in the right place on the branch, the plant will be able to heal itself. If you put a sealant on the cut, all you are doing is creating a hospitable area for bacteria and fungi to grow—wet and dark. Even if you remove too much of the branch for the branch collar to grow back and seal the wound, eventually plant cells on the exposed area will dry up, die and form a natural barrier.
Myth: “Topping” trees (removing most of the branches, and lowering the height of the tree) will make the tree less of a hazard in storms.
Fact: Pruning stimulates growth, and removing all of the terminal buds of a tree by topping it will stimulate massive, rapid growth. This growth is likely to be very weak, and thus more of a hazard than leaving the tree alone.
Myth: You will kill a tree or shrub if you prune it at the wrong time.
Fact: It is much more likely that you will kill a tree or shrub by doing something else to it than by pruning it at the wrong time. Pruning at a time other than what is best for the tree can cause damage, but won’t generally cause death.
Myth: You don’t/can’t prune perennials.
Fact: You can prune perennials. It is just a matter of taste. In the book The Well-Tended Perennial Garden, author Tracy DiSabato-Aust lists the time and manner of pruning for each perennial species she details. Pruning perennials can help delay or stagger flowering and reduce overall height. If you have ever grown masses of Heliopsis, you would find that pruning them in the spring makes overall summer care much more manageable.
The Three-Step Pruning Cut
When pruning branches over about an inch in size, or branches that extend far beyond the main trunk and have quite a bit of weight attached (other branches), this three-step pruning cut technique comes in handy.
Image from Prune with a Purpose by Skip Richter with Texas Cooperative Extension.
The first cut is made on the bottom side of the branch, about an inch away from the desired final pruning cut location. Cut only 1/3 of the way through the branch on this cut. The purpose of the first cut is to sever the bark on the underside of the tree so that when you cut the rest of the branch off, it breaks cleanly at this cut, and does not strip the bark all the way back to the trunk, and down the trunk.
The second cut is made about one inch out on the branch, away from the trunk, from the first cut. This cut should remove the entire branch.
The third cut cleans up the pruning cut and sets the correct angle for the finished cut. It is also more precise, and leaves just enough of the branch outside of the branch collar for the tree to heal itself.
You can prune almost every single branch that requires a pruning saw with this technique.
Goals of Pruning
Whether you are pruning perennials or trees, the goals of pruning are the same:
• Reduce size
• Stimulate lateral growth
• Establish form
• Remove dead wood or plant material
• Promote new growth for development of flowers and fruits
• Open up the canopy to increase air flow and sunlight penetration
The goals of “reducing size” and “stimulating growth” might, at first, seem contradictory. However, pruning generally slows growth of the plant up and out, and stimulates growth within the plant’s framework. Pruning usually results in a bushier, more full plant. Pruning of perennials to stimulate this lateral growth is sometimes called “pinching.”
Pruning Specific Plant Types
Trees, roses, perennials and vines all have different pruning requirements. The timing of blooming also influences pruning.
• Prune spring blooming trees and shrubs immediately after they flower in the spring. These plants flower on “old wood,” and will start growing and setting flower buds for the following year, immediately after blooming. The short window after bloom and before vegetative growth stops is the only time you have to reduce size or shape these plants without sacrificing blooms the following year.
• Prune summer-blooming plants in the winter after the plants are dormant. These plants flower on “new wood” and will push new growth in the spring, along with new flower buds. There is often not enough time between summer flowering and the onset of dormancy to prune before the plants are completely dormant for the winter.
• Prune tea roses by removing branches back to an outward-facing bud. This opens the center of the rose, allowing for better air circulation, and disease control.
• Prune shade trees early in their life to establish a central leader. Pruning during the first 10-20 years of a slow-growing tree will establish its shape for future growth.
• Prune lilacs, forsythias and dogwood shrubs by removing 1/3 of the branches down to the ground level each year. This technique is called “renewal pruning” and keeps plants young and healthy.
• Prune conifers (pine, spruce and other needle evergreens) in the spring when the tips of the branches begin to grow. You can control growth by removing the tips of the branches.
Before you prune any tree, shrub or perennial, it is a good idea to look up specific information about how to prune that specific plant to maximize its growth and maintain its health.
Katie Elzer-Peters is a freelance writer living in Wilmington, NC. Her writing and PR business, The Garden of Words, L.L.C. serves clients all over the world. In her free time, Katie bicycles, surfs, reads books, and, of course, gardens.