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To kill a boxwood bush, you need a combination of physical removal and chemical treatment.
If you’ve got a boxwood bush that’s diseased, overgrown, or just in the wrong spot, knowing how to kill a boxwood bush completely is essential.
Simply cutting it at the base won’t work because boxwood can regrow from leftover roots and stumps.
Here we’ll cover the most effective ways to kill a boxwood bush, from manual digging to using herbicides safely.
Let’s dive into the methods that actually work so you can remove that boxwood bush for good.
How to Kill a Boxwood Bush – The Most Effective Methods
To successfully kill a boxwood bush, you must target both the top growth and the root system.
The following methods are proven to kill a boxwood bush permanently when done correctly.
1. Cut and Dig Out the Entire Root System
The most reliable way to kill a boxwood bush is to remove it physically.
Start by cutting the bush down to a short stump using a saw or loppers.
Then dig a trench around the stump, at least 12 inches out, to expose the roots.
Boxwood has shallow but dense roots, so you’ll need a sturdy shovel or a mattock.
Lever the root ball out of the ground and remove as many root fragments as possible.
Any remaining roots can resprout, so to kill a boxwood bush fully, dig thoroughly.
2. Use a Systemic Herbicide on the Stump
If digging isn’t an option, you can kill a boxwood bush by applying a systemic herbicide.
Cut the bush flat at the base and immediately paint a concentrated glyphosate or triclopyr solution on the fresh cut.
The herbicide travels down into the roots and kills them over several weeks.
For best results, apply within 5 minutes of cutting to maximize absorption.
Repeat the application if you see new shoots emerging later.
This method is very effective to kill a boxwood bush without heavy digging.
3. Smother the Bush with Heavy Mulch or Plastic
You can also kill a boxwood bush by depriving it of light and oxygen.
Cut the bush down as low as possible, then cover the stump and surrounding area with thick black plastic or heavy landscape fabric.
Weigh down the plastic with rocks or soil to keep it in place.
Leave it covered for at least one full growing season to starve the roots.
Smothering works slowly but is a chemical-free way to kill a boxwood bush.
Check periodically for any shoots pushing through and cut them off.
Why You Need to Kill a Boxwood Bush Completely
Leaving even small root pieces behind can lead to regrowth that looks just as vigorous.
Boxwood is resilient and can sprout new stems from buds on the stump.
If the bush was diseased with boxwood blight or volutella, leaving roots can spread the infection.
Killing a boxwood bush completely prevents these problems and saves you work later.
Regrowth from Root Fragments
Boxwood roots store energy and can push up new shoots months after cutting.
To truly kill a boxwood bush, you must either remove all roots or apply a strong herbicide.
Even tiny sections of root left in the soil can send up new green growth.
Disease Control
If your goal is to stop a disease from spreading, a partial kill won’t do.
Killing a boxwood bush completely eliminates the host plant and reduces fungal spores in the soil.
Always dispose of diseased wood by burning or bagging it, never composting.
Step-by-Step Guide to Killing a Boxwood Bush
Follow these steps to kill a boxwood bush efficiently and with minimal effort.
Step 1 – Assess the Size and Health
Determine how large the bush is and whether it shows signs of disease.
This helps you choose between digging or herbicide application.
Step 2 – Cut Down the Top Growth
Use pruning shears or a saw to remove all branches and foliage.
Leave a stump about 4 to 6 inches tall for easier access.
Step 3 – Choose Your Kill Method
If you plan to dig, do it immediately after cutting while the ground is moist.
If using herbicide, apply to the fresh stump within minutes.
If smothering, cover the area with plastic and weigh it down.
Step 4 – Monitor and Repeat as Needed
Check the spot every few weeks for resprouts.
If you see new growth, reapply herbicide or dig out the remaining roots.
Persistence is key to kill a boxwood bush for good.
So, How Do You Kill a Boxwood Bush?
You can kill a boxwood bush by cutting it down and removing the root system, applying a systemic herbicide to the stump, or smothering it with plastic.
The most certain method is digging out the entire root ball, but herbicide is a close second for larger or stubborn bushes.
Whichever approach you take, thoroughness is essential to prevent regrowth.
Now you know exactly how to kill a boxwood bush and can tackle the job with confidence.