When Should You Prune Your Shrubs and Trees? âď¸
If you watch local landscapers and arborists out and about, you may get the impression that itâs fine to prune away at trees and shrubs through the hottest months of the year. But, proceed with caution. For beginners, pruning outside of dormancy can be like tearing pages from a book still being written. By waiting for dormancy, pruning becomes more like editing the book: thoughtful adjustments but without interrupting the story. Today, weâll talk about dormancy and how it relates to decision-making with pruningâŚ
What is Plant Dormancy? And When Is It?
Dormancy in short, is a survival strategy. It helps plants endure tough conditions like winter cold or dry spells. As the days get shorter and temperatures drop, plants shift into a "rest mode," which pauses growth and reconfigures energy exertion. While the plant isnât totally inactive, everything moves at a much slower pace.
Loosely, fall to winter is described as plant dormancy. Some folks avoid early fall pruning because of potentially triggering a last gasp of confusing growth for the plant. Tender new growth wonât appreciate the cold. Other folks might love an early spring pruning near the tail-end of dormancy. Take âfall to winterâ with a grain of salt as dormancy is a gradual fall and rise; it cannot be given a timeframe that neatly fits in a box.
And keep in mind, every species is unique. A single specimen will deal with a particular collection of pests and diseases and have their own growth habits. IDâing your tree or shrub and researching their particular needs is always a good idea. Evergreen trees and shrubs do experience dormancy, just to a lesser extent. A late winter or early spring pruning is recommended for the majority of evergreens.
Why Prune During Dormancy?
Energy Allocation
During dormancy, plants arenât perpetually dealing with leafing out, photosynthesizing, fast woody growth, flowering, fruiting, etc. This makes allocating energy towards pruning recovery all the more manageable.
Disease Prevention & Wound Sealing
Many pests and diseases are dormant themselves during winter. Pruning at this time can reduce the risk infestation and/or spreading of certain diseases. Cuts made during dormancy also have time to activate the sealing process before the busy season is upon them.
Improved Visibility
With no leaves on the trees, it's much easier to see the woody structure â also called the canopy shape. This makes it simpler to identify dead, damaged, or diseased branches and to shape the tree properly. Itâs no wonder the educational pruning graphics show dormant trees! (see below)
Depending on the species, there may be specific pruning practices and canopy shape. However, the common denominator, no matter what, is pruning away the three Dâs â dead, damaged, or diseased.
Some Exceptions
Dormancy pruning is a tried-and-true method because it prioritizes stress mitigation and promotes woody growth. That said, there are other factors that we prioritize with our plants and this subsequently has made year-round pruning a common practice. Here are a few exceptions to dormancy pruning that you may stumble uponâŚ
Flowering Shrubs
Pruning flowering shrubs in the fall or winter can remove flowering buds, resulting in delayed or reduced blooms for the upcoming growing season. Since the goal is often to achieve the most robust blooms possible, you will find many people prune flowering shrubs in the spring and summer, tailoring their approach to each specific species.
Fruit Trees
Pruning fruit trees is a different ball game. Youâre dealing with maintaining a specific canopy shape and promoting fruit buds, all while keeping the tree healthy. Many will prune fruit trees in late winter or early spring (just before the budsâ break), when you can both promote growth where you want AND have a great view of your potential fruiting buds. Pruning in the summer is also common to subordinate vigorous growth, maintain canopy shape, and purposefully set locations for future fruit buds.
Health Issues & Emergency Situations
Pruning to remove diseased or damaged wood is crucial for stopping the spread of pathogens or pests, which may occur at any time of the year. Additionally, hazardous branches, broken limbs, or trees at risk of falling due to storms will obviously need to come down regardless of the season.
Dormancy pruning is not a rule, but a consideration.
An experienced pruner can prune through the hottest months and walk that tight-rope with success. But every squeeze of the pruners and pull of the saw is a bit of surgery. Consider dormancy pruning the anesthesiaâŚÂ