| By the Editors of CornerHardware.com
 Whether it contains flowers and foliage or fruits and vegetables, a garden bed is enhanced by edging. Around a bed of ornamental plants, edging focuses the viewer's attention like a frame around a picture. In a vegetable garden, it separates plants from walkways and potatoes from peas.
Edgings can form pathways, hold garden mulch and make it easier to mow close to bed borders. Edging also helps keep invasive garden plants from spreading into the lawn and grass from spreading into the garden.
Four types of edging are most common: wood; plastic or metal strips; brick, stone or precast pavers; and, simplest of all, shallow spade-cut trenches. Each has advantages, and you can use different kinds around your property. Before discussing their individual merits, let's look at how to lay out a bed, a process that's the same for all types of edgings.
Laying Out a Garden Bed
Beds are easy to lay out on the ground. The difficult part is deciding on the shape you want. Vegetable gardens are traditionally grids with plants laid out in rows, whereas ornamental beds can be any shape, from strictly geometric to completely free-form. Increasingly, though, vegetable gardeners are busting out of the box with their bed designs. Perhaps they're taking a cue from herb gardens, which have for centuries been planned to please the eye as well as the taste buds. And why not? Vegetables are a cornucopia of shapes and colors. They may not be as flashy as flowers, but they're just as interesting. For that matter, you might want to mix the two—say, flowering annuals and perennials with tomatoes, squash, lettuce and corn.
Once you've decided on how you want your bed to look, perhaps by drawing it on graph paper first, it's easy to establish the bed's outline on the ground. Use stakes and string to mark straight lines, or make circles and arcs by using a stake to mark the center of the circle and string to mark the radius. For free-form curves, tease a length of flexible garden hose to just the right shape.
When you're pleased with the shape you've come up with, "draw" the outline by sprinkling garden lime along the strings or hose. (Garden lime is a powdery white mineral available at garden centers.) After you've outlined the shape with lime, you can remove the strings or hose to make it easier to dig. In most cases, it's best to dig and prepare the soil in the bed before installing the edging. If your bed is well-established and the soil is friable, however, you can install edging with very little digging.
Spade-Cut Edging
A shallow trench dug around the perimeter of the bed is the simplest edging to install. Done neatly, it can also be one of the most elegant. Many of the beds and borders in much-admired English gardens, for example, have spade-cut edges. Spade-cut edges work well on any site, sloped or level, with beds of all shapes and plantings of all types.
The best spade for this job is one with a flat blade and straight cutting edge. Many people find a short, D-handled model most comfortable. Unlike turning over soil for a bed, cutting the edge doesn't involve moving a lot of earth. The end result depends on accuracy—making straight lines straight and curves fair and smooth. Sharpening the cutting edge with a flat file will make work easier and produce crisper lines.
Dig carefully along the limed outline, making a trench 3 or 4 inches deep. If the soil is not firm, angle the spade to between 60 and 75 degrees rather than moving it straight up and down. Toss the soil into the bed, and compost clumps of grass or weeds you remove. When you've cut along the entire perimeter, use a garden rake to create a neat trench, sloping the soil up into the bed.
Spade-cut edges need regular but simple maintenance. Keep mulch out of the trench and pull any weeds that sprout in it. A weeding tool works well for this. To keep the lines sharp and crisp, you may need to recut the edge in the spring and fall. This will enlarge the bed slightly, but you needn't remove much soil when recutting.
 Strip Edging
This edging variation forms a shallow, below-ground barrier. Properly installed with only its top edge visible, strip edging is an unobtrusive way to define a bed and separate lawn and garden. It's commonly used with ornamental plantings. Cold winters may dislodge strip edgings or heave them partway out of the soil, so this edging may also require a little maintenance.
Strip edgings come in two common forms, plastic and steel. Plastic strip edging is 5 or 6 inches wide and sold in 10- to 25-foot lengths. Lightweight and fairly flexible, it's a good material for edging beds on flat or gently undulating sites, and it's easy to bend around curves. Steel edging is sold in 4- to 6-inch widths and 10- to 20-foot lengths and several gauges, or thicknesses. It's heavier, more expensive and less flexible than plastic edging, but you can bend it around most garden curves. Use it only on relatively level sites. Frost-heaved or poorly installed steel edgings can be a danger to children and lawn mowers.
To install plastic or steel edgings, start by digging a shallow trench. With a flat spade, cut through the undisturbed soil around the perimeter of the bed. Dig straight down, not at an angle. For plastic edging, dig deep enough to position the bottom of the edging's round lip at the soil level. Position the top edge of steel strips at soil level.
Setting the edging in place will be much easier with at least one assistant to help position it against the straight wall of the trench. Fix plastic edging in place by driving long, thin stakes through the upturned bottom edge of the strips. (These spikes are sold with the edging.) Most of the time, you can just press the stake in with your foot—much easier if you're wearing boots. Secure steel edgings by driving stakes through prepunched holes in the strips or by driving long bobby-pinlike bent spikes over the strip. If the soil is hard, use a hand sledge. With the edging in place, rake garden soil against the edging, leaving it an inch or so lower than the soil level on the lawn side.
Edging of Brick, Stone or Precast Pavers
Edgings of these materials are used as much for their decorative as their practical qualities. You can choose an edging material to complement materials used on your house, nearby walkways or walls. Installing the edgings vertically makes a deeper barrier that reveals only the narrow ends of the bricks, pavers or stones. Laying them horizontally creates a wider, flat surface on level with the soil line, which makes a convenient track for lawn mower wheels and ensures a tidy mowed edge around a bed. Such edgings are often called mowing strips. Edgings of brick, stone or precast pavers can be used on any terrain and with any kind of planting.
 With brick, there's a wide range of colors and textures to choose from. If you're considering using recycled brick, remember that not all brick is made to withstand prolonged exposure to the elements. If you buy new, look for brick or bricklike pavers made for landscape use. Stone also varies widely in looks and durability. Dressed stone with flat, rectangular faces may be appropriate for formal beds. Field stone in random sizes and shapes has a more casual feel. Precast pavers have the advantage of uniform size and being made specifically for outdoor use.
 To install vertical edgings, place the pieces edge-to-edge in a trench cut as deep as the material requires. For horizontal edgings, lay the materials on a sand base, which helps make a flat surface and cushions the bricks or stones, mitigating the effects of frost heaving. Both installations are straightforward, and if you need to cut pieces of edging, you need only a few tools. You can get by with a brick hammer or a brick set and a hand sledge, as shown in the animation. Safety glasses are a must for this kind of work, and heavy gloves and knee pads make it almost pleasant.
In the undisturbed soil at the edge of the bed, dig a trench as wide as the material you've chosen. Its depth should be the thickness of the edging material plus 2 inches. Fill the trench with 2 inches of sand. Tamp it down to prevent settling, then level it. Lay the bricks (or stones or pavers) on the sand, their top faces flush with the soil surface. Add or remove sand as necessary to accommodate variations in thicknesses. Carefully rake the soil in the bed against the bricks. Complete the job by sweeping sand into the gaps between bricks, which will help hold them in place. |
