Lawn trimming around borders, walkways and fences adds to lawn maintenance time. Besides the cost, weed trimmer string constantly beating against the bottom of the fence wears away the string quickly and can damage the fence, especially if you have a wooden or vinyl fence. Mulch edging applied under and next to fencing eliminates the need to trim around the fence. When the edging is set even with the soil to create a mow edge, you can mow directly over the edging.
Cut an edging line through the turf layer and into the soil along the entire fence line, about 6 inches away from the fence. Follow the fence as a guide and step onto the border spade to cut through the turf. Ask your neighbor for permission to access the opposite side of the fence, if you wish, or cut only on your property.
Remove all the turf inside the cut border line and under the fence. Dig out a trench roughly 6 inches deep.
Line the bottom of the trench with permeable landscaping fabric, sometimes called weed barrier. Trim the edges with scissors. Overlap the edges of separate pieces by about 6 inches to prevent weeds from growing through the gaps. If you have difficulty holding the fabric in place against the sides, push metal anchors or sticks through the fabric to pin the fabric to the soil.
Place polyvinyl landscape edging or rubber edging strips against the edges of the trench. Hold the edging strips tight against the side of the trench edge and drive 12-inch edging anchor stakes through the edging at a 45-degree angle into the soil on the lawn side of the trench. Use one stake 1 to 2 feet along the fence line. This step is optional, but reduces the need to re-cut the edging line if the grass spreads.
Fill in the trench to the top edge with organic or inorganic mulch. Use inorganic mulch, such as gravel, around wooden fences because organic mulch retains moisture that can cause rot. Gravel heats up faster and allows water to drain easily into the soil, acting much like a French drain so the bottom of the boards don't constantly sit in a pool of water. You can use an organic mulch, such as bark chips, for other types of fence.