Garden/Retaining Wall DIY
Why Install a Retaining Wall?
A retaining wall solves a real, practical problem, like unstable or sloping ground, soil erosion, uneven grade, while simultaneously adding structure and definition to the landscape. Done well, it transforms a difficult area of the yard into something intentional and polished.
Beyond the functional benefits, a well-built wall creates opportunities: tiered planting beds, defined garden rooms, and added visual interest at varying heights. Whether you're working with manufactured units for clean geometry or natural stone for something more organic, the result is a landscape that looks considered from every angle.
How to Start
Walls serve a range of purposes in the landscape, so the first step is getting clear on yours. Is this a structural retaining wall (holding back soil, rock, or the load of a large feature) or is it primarily decorative? How long and how high will it need to be? Are you working with manufactured wall units for a clean, consistent look, or natural stone for something more organic and textural?
Once you've answered those questions, spend some time browsing different styles and designs. Our design booklets at Silverthorn Landscape Supplies are a great resource for getting inspired and narrowing down your options.
Then nail down your measurements: length, width, and height, including all changes in slope or grade along the wall's path.
Sketch everything out before you begin. A simple plan with your measurements and product choices noted makes it far easier to communicate with anyone involved in the build and helps you order the right quantities.
Use our Materials Calculator to estimate how much product you'll need, and feel free to come in or call if you'd like help working through the numbers.
Getting your products: whether picking up or arranging delivery, reach out ahead of time to confirm stock and lock in your timeline.
Tools You May Need
Paper & pen • Tape measure • Stakes & string • Marking paint • Square • Level • Shovel • Wheelbarrow • Rake • Gloves • Chisel • Safety glasses • Knee pads • Rubber mallet • Hose • Hand tamper • Broom
Products You May Need
Wallstone • A-gravel • Limestone screenings
Note: Advanced Performance Bedding (APB) is a two-in-one alternative to A-gravel and Limestone Screenings that self-compacts. Come in or give us a call to find out if it's right for your project.
Additional Machinery (optional)*
Skidsteer • Stone Saw • Vibrating Tamper / Plate Compactor
*Make sure you are qualified to run any equipment you may rent, or have someone experienced with machinery come out and help.
Installation
1. Plan
Review the How to Start checklist and confirm your measurements, product type, and quantities before you do anything else.
2. Preparation
Mark out the excavation area. Before digging, call the appropriate utility companies to locate any buried lines (phone, cable TV, internet, gas, hydro, waterlines, and city piping).
3. Excavate
Excavate 7"–12" deep depending on your project type. Remove all loose soil. The width of your base should be twice the depth of your wall unit. You'll need room for a minimum of 6" of solid base material and at least 3" of the wall unit buried below grade. This is what gives the wall its stability and long-term durability.
4. Base
Add A-gravel to the excavated area, compacting every 2" and grading toward the final project outline. Continue layering and tamping until height requirements are met, keeping the slope away from buildings for drainage (minimum 1" per 10 feet). The gravel base should leave room for the first 3" of the bottom wall row to be buried below grade.
5. Laying Wallstone
With a solid, level, compacted base in place, spread a bed of Limestone Screenings for the wallstone to sit on. Lay the first row of wallstone directly on the screenings, levelling each unit front-to-back and side-to-side. At least 3" of the first row should be below ground level. As you continue stacking, if you're using manufactured stone, start each new row with a half-cut unit to offset the vertical joints and create a much more stable wall.
6. Backfilling
Before adding any backfill, line the inside face of the wall with weed barrier fabric to separate soils from gravels and prevent mud from seeping through. After every two rows of wallstone, add a layer of 3/4" clear gravel as backfill, continuing up to the layer just before your coping.
7. Finishing Touches
Once all the wallstone is stacked and you're ready for the coping (the top finishing row), dry-fit and cut the pieces to ensure a proper fit before applying any glue. Sweep the wall clean, then glue the coping in place. Once the adhesive has fully cured, backfill with soil behind the coping and finish with sod, plantings, or mulch as desired.
Ready to get started? Come in or call us & we'll help you put it all together.