How to build a raised garden bed

Build a raised garden bed from natural rough-cut stone that blends perfectly into the landscape. Using standard tools and a diamond-grit circular saw blade you can build this project in two weekends and it is a suitable project for beginners.

Learn how to build a retaining wall.

Tools required:

• Bucket
• Circular saw
• Cold chisel
• Level
• Rubber mallet
• Safety glasses
• Spade
• Trowel
• Tuckpointing tool
• Utility knife
• Wheelbarrow

Materials required:

• 3m 2×4
• Gravel
• Landscape fabric
• Mortar
• Stone
• Topsoil

If one of your family members loves plants and flowers, why not build this raised bed? It not only allows you to get just the right soil mix for healthy plants but also reduces back strain, because you don’t have to bend over so far to tend it. The natural stone walls also look great and are easy to build. The rough, randomly stacked stone softens with time and weathering, growing more attractive as it ages.

In this project, we’ll show you the easiest, most time-efficient way to build a stone planter that will last for decades. We’ll also offer tips for sorting and placing stones so you end up with great-looking stonework. You can use these techniques to build a raised garden bed of any shape and size.

This project doesn’t require any special skills, but it does require a bit of muscle to lift the stones. The only specialty tool you’ll need is a diamond blade (sold at home centres) in your circular saw. Our 1.2m x 4.8m planter took two of us about 16 hours to complete.

Learn more about how to build a dry stone wall.

Start by marking the planter outline on the ground, using a rope or garden hose. Dry-stacked walls like this are limited to 900mm in height or they could tip over. Call Dial Before you Dig to have underground utilities marked in your yard before you dig and before you have materials delivered, in case you have to move your wall location.

Once you determine the shape and size of the structure, you can order the materials. Take your dimensions with you to the stone supplier, who can help determine the quantities of stone, pea gravel, landscape fabric and topsoil you’ll need. Order 10 percent extra stone so you have plenty to choose from. You can always use leftovers for borders around gardens.

Browse suppliers to find a stone you like. Costs vary a lot among stone types, but just ensure the stone you choose is relatively flat on the top and bottom. The more flat-surfaced and square the stones are, the easier they are to stack. The techniques we show won’t work for rounded fieldstone. You can buy stone capping, which is a special stone for the top course, or use the same stone as for the rest of the planter.

When you’re ordering materials, ask about delivery fees and forklift services. It’s worth the extra forklift charge to have the materials placed right next to the work area. Trust me on this. Our driver couldn’t get his forklift to the backyard at our location, so we had to move everything by wheelbarrow (it took more than 50 trips!).

Follow these 24 tips for planning the perfect garden.

Build the wall on a gravel base for stability and drainage, and cover the back with landscape fabric and more gravel before filling in with soil.

To make placing stones easier, first arrange them into groups based on similar thicknesses and lengths. As you sort them, set aside nice-looking stones to use as capstones. Keep their thicknesses within a 6mm variation. We set aside 82mm- to 88mm-thick stones for our capstones.

Spread out the stones on tarps, rather than stacking them, if you have room. It’ll save you from digging through the piles later to find the stones you want.

Learn more about building a raised garden bed.

• Mark the border of the raised bed with a rope.
• Dig a 20cm deep x 25cm-wide trench next to the rope.
• Level the bottom and create steps to accommodate sloped areas.
• Fill the trench with 10cm of gravel.

Use a square shovel for crisp edges and keep the trench bottom roughly level. Dig the trench deep enough to hold 10cm of gravel and still bury at least half the first course of stone. If the yard slopes, gradually “step up” the trench to follow the slope. Make the steps match the thickness of the stones you’ll use for the first course of stone. Toss the soil from the trench into the middle of the planter area for use as backfill later.

• Set stones on the gravel and check for level.
• Add or remove gravel to form a level base all along the trench.

Once the entire trench is dug, add 10cm of pea gravel. As you add the gravel, place a stone over the top every 30cm or so and check for level. Add or remove gravel (a little at a time) as needed until it’s roughly level. You’ll fine-tune it when you install the first course of stone (called the “base course”).

Check out our guide to stone paths.

• Lay landscape fabric over the gravel, then place the base course of stones over the fabric to keep it in place.
• Check the stones for level.
• Add gravel under low stones and pound down high stones.
• Butt the outside edges of the stones tightly together.

Use the less attractive stone for the base because it’ll be hidden by soil and grass. Check every couple of stones for level. Pound down high stones with a rubber mallet, and add gravel under low stones, placing the gravel on top of the fabric.

• Add a second course of stones, mixing sizes and staggering the joints from the base course.
• Keep the joints tight on the exposed side.

For good-looking stonework, avoid large gaps between stones on the exposed face of the wall.

• Use a 1.8kg hand maul and masonry chisel to knock “burrs” off the stones so they fit more tightly together.
• Don’t worry about gaps inside the wall; they won’t be visible.

You’ll have to cut some stones to fit. Mark the stone and, using a diamond blade in a circular saw, make a series of cuts about 3mm deep along your mark, lowering the blade with each pass until you’re one-third of the way through the stone. (To limit dust, have a helper squirt water from a spray bottle on the blade while you cut.) Then flip the stone over and cut from the opposite side. The cuts don’t have to be perfectly aligned. Tap the waste side of the stone with the maul to break it off. Save the leftovers for filler.

DIY Basics: check out our essential guide to circular saws.