How to Stop Erosion on a Slope or Hill: 7 Tips to Try

Sloped and hilly land is vulnerable to erosion, which can cause a number of issues, including soil damage, poor plant growth, and structural and aesthetic problems. Fortunately, there are plenty of measures you can take to prevent it from washing away your yard. Below, we’ll explain how to stop erosion on a slope in several different ways, including with mulch, plants, and riprap.

1. Use Mulch as a Preventative Measure

Laying mulch is one of the easiest ways to stop erosion on a hill. Keep in mind, though, that this only works for slopes of 33% or less. You’ll start by calculating how much mulch you need. Then, you can buy the mulch from a nearby home improvement store or have it delivered by a local supplier.

Before laying the mulch, you should remove any weeds on the slope. You might also want to use a pre-emergent herbicide to prevent future growth. For effective erosion control, the mulch layer should be between 3 and 4 inches thick.

2. Set Up Landscaping Rocks 

Like mulch, landscaping rocks are another simple way to manage erosion on a slope. To install them, you’ll begin by removing any weeds on the hill (and, optionally, applying an herbicide). You can also install landscape edging to keep the landscape rocks in place. Then, using an iron rake, spread the landscaping rocks along the ground. It should be 2 to 3 inches deep.

3. Plant Ground Cover Vegetation or Deep-Rooted Shrubs

Ground cover plants and shrubs can also stop erosion since their roots help keep the soil in place and protect it from movement. Plus, they can add an extra touch of natural beauty to your yard.

Just like mulch and landscaping rocks, adding ground cover plants or shrubs is a DIY-friendly landscaping project. Clear the hill of any weeds, then lightly till the soil before planting if your slope is 33% or less. (Don’t till the soil if you have a steeper slope because it can worsen erosion.)

To prevent overgrowth, you can install landscape curbing along with your plants. If you do, you’ll want to place it where the ground cover meets the grass or garden beds. Once the plants are in the ground, take time to water them each day until they’re well established.

4. Use an Erosion Control Blanket

Like mulch, an erosion control blanket sits on top of the soil. Once installed, it helps keep the soil in place underneath the blanket but lets runoff flow over it.

Like the other erosion control methods we’ve mentioned, you’ll need to clear the slope of any weeds and debris before installing one of these blankets. If you have a large hill, forestry mulching is a quick and convenient way to do this.

The next part of the process is a little more complicated. It involves digging a trench, securing the blanket with ground staples, and working the blanket around shrubs and trees. If that doesn’t sound appealing, this is a project to hand over to a local landscape grading pro.

5. Install Riprap Next to Natural Bodies of Water

Riprap is a layer of large rocks and stones that sits next to moving bodies of water, including oceans, streams, and rivers. Its primary purpose is to stop erosion, but it’s also used in stormwater management systems.

Riprap rocks are big and heavy, so it’s best to hire a professional for this method. In most cases, they’ll have to use heavy equipment to get the rocks in place. Plus, depending on the grade of your slope, they might also have to regrade the land.

6. Build a Retaining Wall 

Adding a retaining wall is another way to stop runoff from flowing downward and causing erosion. If you’re a confident DIYer, you can build a retaining wall yourself. Otherwise, it’s best to bring in a pro—especially if the wall is more than 3 feet tall.

If you’re curious about the process of building a retaining wall, here’s a quick summary. It starts with measuring and marking the location of the wall, then digging a trench and filling it with gravel. For the wall itself, a pro will lay rows of staggered concrete blocks and top everything off with a layer of capstone blocks.

7. Design an Exterior Drainage System

If you have an extreme slope or your area receives significant amounts of rain, you should consider hiring a pro to install an exterior drainage system. A French drain, for example, can reroute water from the upper part of a slope to a safe drainage location on your property.

Installing a French drain is a labor-intensive project that requires numerous tools and supplies and some heavy-duty equipment. It’s a complicated job that very few DIYers are equipped to handle.