The transition between different elements within a yard is a place where gardeners may feel challenged with plant growth and with the element of design. What you put into the space or how you manage it is referred to as the edge or edging. You might hear gardeners ask each other how they edge their vegetable or flower gardens, landscape beds, sidewalks, driveways, patios or other unique landscape features.
The best options for edging depend considerably on the situation at hand and gardeners’ personal preferences. Some gardeners prefer a natural border between elements, where grass from the lawn creeps into the landscape and landscape plants creep onto the sidewalk. Others prefer a formal approach with bricks or stones lining every path and landscape bed, and a large group is somewhere in the middle of these informal and formal approaches.
A natural border or natural edging is easiest to maintain where there are two elements that coexist next to each other without a lot of infringement from either side. For example, where the lawn meets the sidewalk, or where the mulched area around a tree meets the lawn. The grass may creep in or on the other elements but is fairly easily maintained within its own space with the occasional help of a shovel or string trimmer.
To get a clean edge to start the season, use a flat-bladed shovel. One preferred model is referred to as a garden spade. The blade is rectangular, the handle is a little shorter than that of a digging shovel, and there is a D-shape on the handle end for better gripping.
If using the shovel to define an existing edge, say between a turf and mulch, insert the blade of the shovel into the ground vertically at the transition point to create a slice between the two. In this example, you may wish to make the soil line in the mulch area lower than that of the grass to keep the mulch contained. If this is the case, you might wish to position the shovel horizontally, then angle it to the desired level and slice of sections of soil as needed.
If using the shovel to create a new edge, such as when creating a new landscape bed within a lawn, use the same technique but take care about the placement of the edges. Tight corners may be difficult to mow or keep mulch contained. An old gardening trick when creating new beds is to lay out a garden hose in the shape you desire, then see if you can drive the lawn mower around it easily. The garden hose also offers a nice visual prior to digging to help you get a design that fits.
For more formal edges, options include plastic, metal, wood, concrete, brick and stone. Each of these should be set slightly into the ground to prevent movement and avoid becoming a trip hazard.
Plastic is the least expensive. There are a few different grades of plastic edging. The most common is a long flat strip with a roll along one edge meant to be the top. The flat-bladed shovel will come in handy to make a slit or trench to insert plastic edging into. It is an easy option, but does little for aesthetics and eventually will need to be replaced as the plastic breaks down.
Metal edging is also in long flat strips, typically 4 inches wide by 10 feet long with pockets to insert little metal stakes that help hold it in place. Look for it at larger garden centers or landscape suppliers. Metal edging is an especially good choice when you want to contain gravel or mulch with very little attention given to the transition.
Landscape timbers are next up for a natural but contained look. They will draw more attention than plastic or metal edging but detract little from the landscape. The downside of using landscape timbers is that curves are impossible without a lot of cutting. They do work well for straight passes, such as along a driveway, sidewalk or straight path.
Concrete edging refers to pre-formed concrete crescents and scallops designed specifically to be pieced together to line landscape beds. They have their own look that may be undesirable to some, but they get the job done. Set them into the ground with the desired amount exposed. Although concrete will likely outlast the plastic, it also will eventually need to be replaced as moisture and the freezing/thawing process break it down.
Pavers and retaining wall blocks are also made of concrete and may be used for landscape edging. They are usually a little sturdier than other concrete edging and create a real statement as a transition point. Pavers and retaining wall blocks are available in a great range of styles and colors to fit any landscape.
Bricks and stone are the most permanent options and offer the most for styling for a more formal look in the garden. Try setting them on the long end, short end, flat side, or angled into the ground for different looks.
— Jennifer Smith is a former horticulture extension agent for K-State Research and Extension and horticulturist for Lawrence Parks and Recreation.