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To keep a crepe myrtle from growing back, you’ll need to physically remove the stump and root system or apply a potent herbicide to the freshly cut surface.
That’s the honest truth because crepe myrtles are vigorous growers with a stubborn root system that loves to resprout.
If you cut the tree down and simply walk away, you’ll almost certainly see new shoots popping up from the stump within weeks.
So if you’re tired of fighting those suckers and want a permanent solution, this guide will show you exactly how to keep a crepe myrtle from growing back.
In this post, we’ll cover different methods for how to keep a crepe myrtle from growing back, including chemical and non-chemical approaches.
Let’s dig in and get that yard clean for good.
Why Crepe Myrtles Keep Growing Back So Aggressively
The first step in learning how to keep a crepe myrtle from growing back is understanding why it fights so hard to survive.
Crepe myrtles store massive amounts of energy in their roots and the base of the trunk.
When you cut the top off, those roots don’t know the tree is gone.
Instead, they send up new shoots, called suckers, to try and regrow a new trunk.
This survival mechanism is exactly why a crepe myrtle from growing back becomes such a persistent problem for homeowners.
The tree is basically hardwired to resprout after any kind of damage.
So you can’t just chop it down and hope for the best.
You need a deliberate plan that targets the root system itself.
1. The Root System is Massive and Deep
A mature crepe myrtle’s root system extends far beyond the drip line of the tree.
These roots aren’t just shallow feeders either, they go down several feet into the soil.
That means even if you pull up every visible shoot, hidden roots underground are still holding energy reserves.
This is why a crepe myrtle from growing back keeps happening no matter how many times you cut the sprouts.
The roots are simply too large and too well-established to die from neglect.
2. The Stump Contains Dormant Buds
The stump itself is packed with dormant buds that are just waiting for a signal to activate.
Cutting the trunk triggers those buds instantly.
It’s like a wake-up call to the entire root system.
So if you want to keep a crepe myrtle from growing back, you have to deal with those buds directly.
Just sawing the trunk to ground level won’t remove them.
Those buds are encoded to sprout no matter how low you cut.
How to Keep a Crepe Myrtle from Growing Back with Herbicide
The most effective and reliable method to keep a crepe myrtle from growing back is using a herbicide specifically designed for stump treatment.
You’ll want a product containing glyphosate or triclopyr, as these are systemic chemicals that travel down into the roots.
Here’s the step-by-step process that actually works.
1. Cut the Trunk Down First
Start by cutting the crepe myrtle trunk as close to the ground as possible.
Use a chainsaw or a handsaw for a clean, flat cut.
The fresher the cut, the better the herbicide absorption will be.
Timing matters here because tree movement and sap flow are highest during active growth.
Late summer or early fall is the best time to do this, as the tree is pulling energy down to the roots for winter storage.
That’s when the herbicide gets carried deep into the system, helping you keep a crepe myrtle from growing back for good.
2. Apply Herbicide Immediately
Don’t wait more than 15-30 minutes after cutting to apply the herbicide.
If the cut surface dries out, it seals off the vascular tissue and blocks the chemical.
Paint the entire cut surface generously with a brush or spray bottle.
You want it saturated but not dripping into the soil.
This direct application is the real secret to stopping a crepe myrtle from growing back.
3. Drill Holes for Extra Penetration
If the stump is large, drilling holes into the top and sides helps the herbicide reach deeper.
Use a drill with a half-inch bit and make several holes at an angle.
Then pour the herbicide directly into those holes.
This method is called the drill-and-fill technique, and it’s a powerful way to kill the entire root system.
It ensures even the deepest roots get a dose of the chemical, making the process of stopping a crepe myrtle from growing back much more complete.
Non-Chemical Ways to Stop a Crepe Myrtle from Growing Back
If you prefer to avoid chemicals, you still have options to keep a crepe myrtle from growing back.
These methods take more elbow grease and patience, but they’re completely doable.
1. Dig Out the Entire Stump and Root Ball
The only guaranteed non-chemical way to stop a crepe myrtle from growing back is to remove the whole root ball.
You’ll need a shovel, a pickaxe, and possibly a mattock for the bigger roots.
Start by digging a wide circle around the stump, at least two feet out.
Then cut through the lateral roots with an axe or saw.
Finally, rock the stump back and forth to loosen the taproot and pull it up.
This is hard work, but it’s 100% effective because there’s nothing left underground to sprout.
The key is to be thorough because any root fragment left behind can regrow into a new tree.
2. Smother the Stump with Black Plastic
Smothering is a slower but effective method.
After cutting the stump low, cover it completely with a thick sheet of black plastic.
Weigh down the edges with rocks or bricks to keep it airtight and block all sunlight.
Without light, the stump can’t photosynthesize and produce new growth.
Over several months to a year, the stump will eventually rot and die.
This method works best if you’re not in a hurry and want to naturally keep a crepe myrtle from growing back.
3. Boiling Water and Epsom Salt
This is a folk remedy that can work for smaller stumps.
Pour boiling water directly onto the fresh cut stump.
The heat will kill the living tissue at the surface.
Then pack the stump with Epsom salt, which draws moisture out of the wood and roots.
Cover it with plastic to keep the salt in place.
This won’t be as effective as digging or herbicide, but it can help slow down and eventually stop a crepe myrtle from growing back if the stump is young and small.
Common Mistakes That Cause Crepe Myrtles to Regrow
Even with the best methods, people still fail to keep a crepe myrtle from growing back because of a few simple mistakes.
1. Cutting the Stump Too High
Leaving a tall stump gives the tree an advantage.
A higher stump retains more stored energy and more buds.
Always cut as low as possible, ideally at or below soil level.
The lower you cut, the less energy the tree has to push out new shoots.
2. Not Treating the Suckers While They’re Small
If you see new shoots, don’t prune them with shears and leave the stubs.
That actually encourages more growth.
Instead, pull the suckers off by hand when they’re young and tender.
Or apply a small amount of herbicide directly to the leaves of the suckers.
This systemic approach will pull the poison down into the roots and help you keep a crepe myrtle from growing back.
3. Using Herbicide at the Wrong Time of Year
Applying herbicide in the spring when sap is rising upward can trap the chemical in the stump.
That’s why late summer and fall are the ideal seasons.
During those seasons, the tree pulls resources downward, which carries the herbicide into the roots.
Timing your application correctly is half the battle in learning how to keep a crepe myrtle from growing back.
So, How Do You Keep a Crepe Myrtle from Growing Back?
You keep a crepe myrtle from growing back by removing the root system entirely or by applying a systemic herbicide right after cutting it down.
The quickest and most reliable option is the herbicide, but digging it out is the only fully natural solution.
Either way, consistency is your best friend because you have to be vigilant about any suckers that pop up.
Don’t get discouraged if you see a few shoots after your first attempt, just treat them again quickly.
The longer you let them grow, the stronger the root system gets again.
So take action now, follow the steps we laid out, and you’ll finally stop a crepe myrtle from growing back in your yard.
Your landscape will look cleaner, and you’ll save yourself years of frustrating regrowth battles.