A neatly edged flower garden gives your yard a polished appearance. Even better, it can help reduce weeds since lawn grass can't easily invade your flower bed. The simplest form of edging requires no special materials but still provides a crisp and effective edge. Dug edgings, called trench edging, use a trench around the perimeter of the bed to prevent grass and weeds from spreading into the garden bed. This edging method does require some upkeep, but it provides a quick, low-cost and versatile option for finishing your garden.
1 Lay a garden hose or twine around the perimeter of the bed to mark the edging line. Place the edging at least 12 inches away from perennial plants to avoid cutting through roots when you dig the edge.
2 Push the blade of a flat spade into the soil 4 inches away from the outside of the marked bed perimeter. Push the blade into the soil 6 inches at a 45-degree angle. Work around the entire outside of the bed as you make this initial cut.
3 Make a second cut with the spade directly against the marked perimeter. Hold the blade of the spade perpendicular to the soil surface and push straight down until the cut intersects with the first angle cut, removing a V-shaped strip of soil and sod. Repeat until you have made this second cut around the entire perimeter of the bed.
4 Pull the strip of soil and sod out of the the trench. Clean up any rough portions of the edging with a handheld trowel.
5 Remove fallen leaves and yard debris from the trench weekly during your regular lawn or garden maintenance. Recut the edges of the trench in fall and spring to maintain a crisp, weed-free edge.