Concrete provides a stable and attractive material for the edge of your garden. Since concrete is similar to mud, before the concrete dries, if you want to edge your garden with concrete you will need to form a mould. You can create this mould on your garden, letting the concrete harden in place, you can let a machine cast your concrete in a semi-finished state or you can create this mould elsewhere and then move the finished blocks into place.
Garden Edging's Purpose
Edging is defined as the transitional piece between your garden beds and the rest of your landscape. Edging will help stop grasses and weeds from moving into the garden bed and it will also help walkers through your garden to stay on paths and out of your beds. You can create edging out of a number of hard materials, depending on how you want your garden too look. The smooth, crisp lines of concrete edging gives your garden a professional and manicured look.
Regardless of the type of concrete mould you will be using, the first installation step is digging a trench. The trench will not only provide a base for your concrete, but it will also prevent grasses from growing underneath the mould and encroaching on the garden bed. Before you dig, you will want to mark out the trench. Use stakes and string to make any straight lines and use a garden hose to mark out any curved lines. Make the trench about twice as wide as you will want your concrete edging.
Creating Your Own Molds
Creating a concrete mould is as simple as forming two wood walls along the trench. Install the wood at least 2 inches into the dirt at the bottom of the trench, to prevent the concrete from seeping out underneath. Additionally, install stakes behind the wood every foot or so and screw the stakes to the wood to give it some extra support.
Straight edging is fairly easy to set up but if your garden edging curves, you will need to make cuts on the back side of the wood. Make the cuts every 1/2-inch and make them about halfway through the wood. This will allow the wood to bend slightly so you can conform it to your trench. Once the mould is on place, mix the concrete and pour it in. Once the concrete has cured, remove the stakes and the wood, leaving just your concrete.
Using a Curbing Machine
If you like the idea of a solid concrete garden edge, but don't want to go through the hassle of building a mould, you can use a curb machines to do the job for you. Start off with a trench a few inches deep. Mix your concrete and pour it into your curb machine. Line the machine up with your trench and as you move the machine backwards, a concrete curb comes out of the opening in the bottom. Use a putty knife to cut the concrete every few feet, so that expansion in the concrete won't crack the curb.
Precast Concrete Molds
Concrete also comes in precast forms, available at most garden centres, or you can make your own. The general process is the same, you just have to make the blocks in a wooden cast that you put together. This process allows you to vibrate the concrete after you pour it, which forces out air and makes the concrete much stronger. You'll still have to dig the trench, but then you simply have to place the precast blocks into the trench and you're done.