To prune or not to prune? That is always a serious question to ponder for many homeowners, gardeners, landscapers and property owners. Many people consider the NO. 1 winter garden task to be pruning plants annually. Yet, most do not understand the basic principles of pruning, its dramatic effects on plants nor the actual reasons for it. Let’s take a moment to examine this horticulture exploit to provide a better understanding of pruning plants.
After working as a horticulturist with the Extension office for more than 20 years now, it is my professional view that most ornamental plants really do not need pruning. They by far look and perform better if left alone and untouched. Many homeowners and landscape professionals are mistakenly convinced that annual pruning is the right thing to do and may base this urge on outdated horticulture recommendations.
Before pruning any plant, one must have a really valid horticulture supported reason for doing so. Otherwise, all other motivations to prune, including it being part of a yearly ritual, are frankly unjustified chores. One could be doing more harm to the plant than good.
In reality, the idea of pruning has become mostly a short-term fix or excuse for the real problem – wrong place and poor plant selection.
Many people make the mistake of buying and setting out a plant and not realizing how large it will get. Or they trust and pay some professional landscaper to know what they are doing.
Pruning then becomes a required routine or job because the shrub or small tree was unwisely planted way too close to a building or window based on its mature size. In due time, the plant naturally overgrows its limited space.
The common excuse here is usually, "I did not know it was going to get that big."
Crape myrtles destined to be beautiful small trees are whacked back each year or "crape-murdered" to control their size. Hollies planted way too close together and charged by the hole soon consume each other and must be constantly sheared back. Large azaleas placed under windows have to be trimmed and beaten back annually. Many attractive landscape trees have to be butchered and ruined to keep them from growing large and getting into utility lines.
All these plants should have been planted elsewhere, or another type or smaller variety should have been chosen. Poor plant selection and planting blunders do not justify pruning. Such mistakes require more maintenance and more money that never ends.
Before selecting a plant and putting it in the ground or allowing a professional to make the mistake of planting it, find out how large it will reach at maturity. Most plants come with labels that list mature size and recommended spacing distance.
Many of our favorite plants now have small and large varieties to accommodate any situation. You will do a lot less pruning and correcting mistakes if you do your homework.
If it is necessary to prune a plant, these are some basic pruning rules and guidelines to remember:
Plants that bloom on a new year’s growth, or after May, should be pruned in the winter when dormant, during the months of January to early March. This includes all hollies, boxwoods, crape myrtles, most roses and fruit trees.
Plants that bloom on last year’s growth, or before May, should be pruned after they finish blooming, as is the case with camellias, forsythia, loropetulam and azaleas. The exception to this rule is hydrangeas. French and oakleaf hydrangeas bloom on old wood, so prune after they flower. Peegee and smooth hydrangeas bloom on new wood, so prune before new growth or as it begins in the spring.
Local in Effect
Plant regrowth usually occurs within 6 inches of any pruning cuts made. Pruning almost always stimulates a response in growth and possible multiple new shoots. Note this fact when wanting to prune to control and limit growth. Routine pruning causes more growth, and thus, more labor.
Heading cuts describe random pruning made anywhere along a stem or branch, typically done to control height and shape a plant.
Commonly performed as shearing, as done with hollies and boxwoods, heading cuts remove the terminal portion of shoots or limbs and trigger many buds left behind to break dormancy and grow. This pruning technique is used to force branching or more dense regrowth.
Thinning cuts are individual pruning cuts that remove an entire shoot or limb to its point of origin from the main branch. These cuts are made 1/4 above a bud or to a crotch or lateral branch inside the plant's canopy. This method prevents the normal flush of regrowth and hides the cuts from view. Thinning cuts are recommended if pruning and shaping large-leafed plants like Japanese cleyera, specific hollies, gardenias, azaleas and camellias. Thinning cuts are best for maintaining woody plants in their natural form.
Renewal pruning is a drastic pruning method that involves cutting the entire plant back to within 6 to 12 inches of the ground. If and when this is necessary, it is best executed in March just before the first spring flush of growth. Typically recommended for most roses, some grasses, specific perennials and on occasion, other large plants to control height or rejuvenate from damage. Junipers and boxwoods should never be pruned to stubs as they do not have the ability to sprout back.
Cutting back the top limbs out of the large shade and pecan trees is not recommended. Topping makes trees look ugly. Doing so eventually causes vigorous sprouts to grow from the cuts. They are weakly attached to the tree
Topping can also result in limb decay and dieback.
The purpose of placing ornamental plants around our homes, landscapes and businesses are to enhance the beauty and value of those properties. Allowing, hiring and performing wrong and ugly pruning destroys those benefits and ultimately harms the plants we cherish. Take time to educate yourself, so you will know when to prune and when to not.
For help on other home and garden questions, contact the local county Extension office or visit us at www.aces.edu.
Basic Reasons for Pruning Plants
1. Prune to maintain a plant's size or form while enhancing its beauty and character. Destroying its natural shape and limiting its growth potential is not aesthetically pleasing. No other reason or rule should result in ugly and tacky plants.
2. Prune to remove deadwood and damage in order to promote a healthy plant. Act immediately if mechanical, disease or insect damage occurs.
3. Prune to increase the air and light circulation. This applies mainly to fruit production in trees and crops. Pruning helps improve flowering, fruiting and helps prevent diseases.
4. Prune to direct, confine growth and prevent potential damage. Correct potential problems such as overlapping and rubbing branches and poor crotch angles.
5. Prune to stimulate new growth. Strategically made cuts can help train new growth, rejuvenate old plants and fill in bare areas.
6. Prune to increase flower and/or fruit production or prune to decrease flower and fruit production. Fruit trees and small fruits are trained and heavily pruned annually to stimulate growth and flowers for maximum production. But the opposite may be done on mature plants in some cases to limit fruit load and limb breakage.
~Shane Harris is the County Extension Coordinator for Tallapoosa County.