Adding berm landscaping to your garden design by building a berm or landscape mounds is an easy and attractive way to add interest to your yard, especially in flat areas.
What is a berm in landscaping?
Building a berm or mound isn’t as complicated as many would think. By following simple guidelines in the design of the landscape mounds and berms, many garden troubles can be eliminated with ease.
If you’re one of those wondering, “How do I make Landscape Mounds and Berms?” read on to get an answer.
- Landscape Berms And Mounds Ideas – Design
- How To Build A Berm Or Landscape Mounds
- Sketch The Landscape Berm Design To Scale On A Graph Paper Beforehand
- Put Down Your Layout Plan
- Remove The Turf Layer In The Marked Lawn
- Fill The Area With Clean Dirt To Build Up The Berm
- Fill The Remaining Few Inches With Clay Soil
- Add Top Soil Over The Clay Layer
- Use A Shovel To Flatten The Top Soil Of Your Berm So That It Can Take A Good Shape
- Naturalize Your Berm
- Plant Your Vegetation
- Add Mulch Around The Plants
- The Bottom Line
In this article, we’ll dive deep into all the details of garden mounds and berm landscaping ideas.
Landscape Berms And Mounds Ideas – Design
Before building landscape berms or mounds, a landscape designer should first plan its design. You can also design it for yourself.
Always consider the mound’s overall purpose in advance and the drainage patterns within your landscape. One “purpose” could be a spill containment berm.
On average, a garden berm or mound should be about four to five times longer than its height, progressively streaming out into the remaining landscape.
Most landscape berms have a height of 18″-24″ inches. The berm design can have more than one peak to give it added interest and shape to perform its purpose.
Most of the landscaping berm are given a curved or crescent-looking shape, which is preferable and natural looking.
Related: 37 Landscape Edging Ideas
How To Build A Berm Or Landscape Mounds
Dirt berms are often constructed using layers of soil and fill material such as plant debris, sand, asphalt, soil, or rubble.
Use the fill materials to fill the major part of the berm, forming its shape around it using soil. Firmly tamp the fills to ensure compactness.
The LandscapingNetwork has this Pro Tip:
When grading mounds near existing trees and shrubs, never alter the grade or disturb soil within a tree’s drip line.
Also, be sure the berm will not interfere with or create potential drainage issues with water that has previously supported the life and health of the tree.
The Following are the Items You’ll Need to Have When Building Landscape Mounds and Berms
- Graph paper
- Landscaping spray paint
- Garden hoses
- Clay soil
- Fill material dirt
- Boulders and flagstones (optional)
- Shredded bark mulch
- Various plants
The Following Ten Tips for Building Landscape Mounds and Berms Will Guide You Better
Sketch The Landscape Berm Design To Scale On A Graph Paper Beforehand
Having a sketch of the berm to scale will help you become aware of the area the berm will occupy so that you can know whether you have enough room to build it.
What are some of the best plants for berms?
Berms meant to showcase trees should take a horizontal slope of 5′ to 7′ feet with a 1-foot height from the base, while those meant to showcase small plants can do well on a steep slope of 3′ to 4′ feet in length with a height of 1′ foot.
To build a berm, outline its shape and dig up any grass. Next, add the desired fill to the excavated area and begin packing around it with soil.
The peak of your berm should be designed to occupy one end instead of taking the center position. Also, the top of the berm should be flat to prevent water from running off to the sides of the slope.
Be creative with the design, such that your berm has multiple peaks, undulant conical edges, or even a crescent shape rather than the perfect oval shape.
Put Down Your Layout Plan
Lay out the entire berm shape on the ground using the garden hose; garden hoses are preferred because they flex easily and help achieve perfect curves to layout an island bed and offer flexibility in the design.
Work inside the outline, removing all of the sod using the spade. Then, remove all topsoil left in the area after digging out the sod.
After you’re content with the shape of the berm, transfer it to the lawn using landscaping spray paint.
Expand the base about five feet out in width for every foot the berm rises up. This is a 5:1 ratio, and it’s just an average for what people use when they build a berm.
Remove The Turf Layer In The Marked Lawn
Use your spade to remove the turf clutter so that the marked turf is now ready for refilling. Curve it with grass, if possible, so that you can be able to see your design as you fill it up with dirt.
Fill The Area With Clean Dirt To Build Up The Berm
Use a garden hose to spray the mound so as to moisten the soil and then tamp it tightly. The fill dirt should take up about half of the total height of your berm. The remaining part should be filled with topsoil.
Fill The Remaining Few Inches With Clay Soil
Depending on the height of your berm, cover up the fill dirt with 1 foot of clay soil. Any other correction in the berm design should be made using clay soil.
Clay soil is preferred as it compresses well, and soil erosion is not likely from runoff water.
Add Top Soil Over The Clay Layer
Bulk up the remaining height of your berm using topsoil; this will provide nutrients for your vegetation.
Then you should use clayey soil (not gravel or rubble) as a second top layer. Clay is a type of soil that is more impervious to water than is fill, so your topsoil won’t percolate through it.
Spray it with water to remove air pockets. How thick this layer needs to be varies depending on plant size. In the worst cases, you may have to install a drainage system.
Use A Shovel To Flatten The Top Soil Of Your Berm So That It Can Take A Good Shape
When starting the process, begin by outlining the shape of the berm with chalk, spray paint, or flour.
Remove the sod and load the bottom of the berm with whatever filling you’ve chosen, and pack down around it with soil.
Drag the topsoil using a bow rake down to the outlines of the berm to achieve a significant slope and smooth edges. Compress the top soil, especially on the sides of the hill, to ensure that it’s compact.
Berms can be made into pretty much any shape, which makes them handy for landscapes that might not have the most traditional measurements, but for a more natural look, stick with the curving shape.
Naturalize Your Berm
Place large boulders and flagstones throughout the grass berm to give it a more natural outlook. Bury one-third of the stone height to hold them firmly in the soil simply to make them appear as natural features on the hill.
Plant Your Vegetation
Plant the vegetation of your choice, be it trees, perennial and annual flowers, groundcovers, and shrubs on the berm, so that they can establish roots to anchor the soil, especially on the sides of the slope.
Plant the short plants at the peak of your berm; this will make them more visible. You can have several trees at the top of your berm as well, but plant them in an irregular pattern so that they can look natural.
Plant the groundcovers at the slope of your berm to help preserve the soil from being eroded.
Add Mulch Around The Plants
Add a 2-3 inches film of mulch around the plants on your berm; use mulches with uneven shapes to prevent erosion. Shredded barks can make good mulch as they interlock to resist washing down the slope.
The Bottom Line
There are no specific rules for building a berm. The landscape outlines will dictate much of the berm or mound’s design, as the rest lies with the owner’s needs and preferences. Be creative and unique.
Berms are mounded hills of dirt constructed to block out unwanted or unsightly views, creating a subtle sense of privacy, directing or redirecting drainage and foot traffic, emphasizing a particular focal point, or adding raised elements to the garden.