Plant Pruning Basics

Many customers share a common fear: they'll prune their plants to death!

Many customers share a common fear: they'll prune their plants to death! We will examine this common refrain more closely today.

The good news is that trees and shrubs are generally very hardy, and while improper pruning might mean the plant doesn’t bloom next year and/or looks ugly for a season or so, pruning is probably not going to kill it.

That said, there are two ways to prune a plant to death, and unfortunately, they’re both fairly common.  

The first way to kill a plant is to over-prune it  

This is really tempting when a shrub or tree is severely overgrown! But remember that the plant needs its leaves to absorb sunlight and convert it into energy. Removing too many leaves messes with that process, and the roots can’t get the energy they need. The rule of thumb is to remove no more than 1/3 during pruning.. 

But keep in mind that even when a homeowner overprunes, it probably won’t immediately kill the plant—it will most likely just force it to send up a bunch of new shoots from the roots and stem. The new growth will be weaker and more likely to be damaged in bad weather. Overall, the plant will be stressed, making it more susceptible to disease. A better solution is gradually reducing the plant, giving it time to recover and adjust before pruning again.

The second way is to shear the outermost layer of leaves repeatedly

Many people do that when they want the plant to maintain a certain shape, like a square or a circle.  While this might have nice curb appeal, it harms the plant because every time they prune off that outer layer, a homeowner forces the plant to produce lots of new, tiny branches near the outermost part of the tree or shrub. 

These tiny branches are the only ones that will produce new leaves, and soon, the plant will have a thin layer of green growth. That’s not sustainable and will eventually kill the plant. Plus, it doesn’t allow air to circulate within the plant, creating an inviting environment for pests and diseases.

A better solution? Well, avoid shearing the plant or pruning it into geometric shapes. Instead, reach deep into the plant, and cut off a few larger branches.  This will open up the plant, allowing more sunlight and air in.  It will also encourage more growth from the middle of the plant.