How To Keep Blackberry Bushes Under Control

Keeping blackberry bushes under control comes down to a simple truth: you have to be more stubborn than the plant.
 
If you’ve ever planted blackberries and watched them swallow a fence line, you already know how aggressive these canes can be.
 
The good news is that keeping blackberry bushes under control is completely doable with the right timing, tools, and a little persistence.
 
In this post, we’ll look at how to keep blackberry bushes under control using pruning, root barriers, mowing, and smart planting habits.
 
Let’s dig in.
 

Why Blackberry Bushes Get Out of Control So Fast

Blackberry bushes get out of control because they spread in two directions at once, above ground and below ground.
 
Understanding this is the first step in keeping blackberry bushes under control for good.
 

1. They Spread by Canes and Runners

Blackberry bushes send up new canes from the crown each year, and those canes arch over and root wherever they touch the soil.
 
That tip-rooting habit is why a single plant can turn into a thicket in just a couple of seasons.
 

2. They Spread Underground Too

Many blackberry varieties also spread through underground stems called rhizomes.
 
That means you can cut every cane to the ground and still see new shoots popping up weeks later.
 

3. Birds and Wildlife Help Them Travel

Birds eat the berries and drop seeds far from your garden.
 
So even if you control the blackberry bushes in your yard, new ones can show up along fences and hedgerows.
 

How to Keep Blackberry Bushes Under Control

Keeping blackberry bushes under control is easier when you work with the plant’s growth cycle instead of fighting it all at once.
 

1. Prune Twice a Year

The single most effective way to keep blackberry bushes under control is regular pruning.
 
Cut back the canes that already produced fruit right after harvest, since those won’t bear again.
 
Then in late winter, thin the remaining canes to about four to six strong ones per plant.
 
This keeps the blackberry bushes from turning into an impenetrable bramble.
 

2. Install a Root Barrier

If your blackberry bushes are the spreading type, a root barrier makes a huge difference.
 
Bury a heavy plastic or metal edging at least 12 inches deep around the planting bed.
 
This stops rhizomes from creeping into your lawn and keeps blackberry bushes under control at the source.
 

3. Mow Around the Patch

Mowing won’t kill established blackberry bushes, but it stops new canes from rooting outside the row.
 
Run your mower along the edges every few weeks during the growing season.
 
This simple habit keeps blackberry bushes from claiming the space around them.
 

4. Grow Them in Containers or Raised Beds

One of the smartest ways to keep blackberry bushes under control is to plant them in large containers or raised beds lined with fabric.
 
The walls of the bed act like a permanent barrier.
 
Just make sure the container is big enough, since blackberry bushes have deep, thirsty roots.
 

5. Pull Suckers Early

When new shoots appear where you don’t want them, pull them while they’re small.
 
Yanking them out by hand when the soil is moist gets more of the root than cutting them does.
 
This keeps blackberry bushes from re-establishing in spots you already cleared.
 

6. Use Mulch Wisely

A thick layer of mulch around your blackberry bushes suppresses weeds but won’t stop rhizomes.
 
Still, it makes it easier to spot and remove stray shoots.
 
Combined with pruning and barriers, mulch helps keep blackberry bushes under control with less effort.
 

Common Mistakes When Controlling Blackberry Bushes

Even careful gardeners run into trouble keeping blackberry bushes under control.
 
Here are the mistakes to avoid.
 

1. Only Cutting the Tops

Cutting blackberry bushes to the ground without digging out the crown just makes them come back thicker.
 
You have to remove the root system or smother it to actually reduce the plant.
 

2. Letting Canes Tip-Root

If you let long canes droop to the ground, they’ll root and create new blackberry bushes.
 
Tie canes to a trellis or cut them back before they touch soil.
 

3. Skipping the Follow-Up

Blackberry bushes rarely give up after one round of clearing.
 
Plan to check the area every few weeks and remove new growth right away.
 
That consistency is what truly keeps blackberry bushes under control.
 

So, How Do You Keep Blackberry Bushes Under Control?

You keep blackberry bushes under control by pruning twice a year, installing a root barrier, mowing the edges, and pulling suckers before they take hold.
 
It also helps to plant blackberry bushes in raised beds or containers if you want less sprawl.
 
And the biggest key of all is staying consistent, since blackberry bushes bounce back fast when you ignore them.
 
With a bit of routine work, you can enjoy fresh berries every summer without letting the patch take over your yard.
 
Happy gardening.