One summer when I couldn't finish weeding an 80-foot-long border of shrubs and perennials, my mother — an avid English gardener — took a good long look before she sighed and gave me this advice: If you don't have time to weed, clean up the edge where the soil meets the grass. Creating a nice, crisp outline — making a sharp V- or L-shaped cut with a straight-edge spade to separate lawn from soil — is like tidying up your house for company when you can't give it a thorough cleaning. A defined edge reads like a well-cared-for garden, even if there's thistle growing among the roses.
"The front edge is so important to the overall first impression of the garden," said Karen Moore of Coventry Gardeners, Westmont, Ill. "I consider the front edge to be the first row of plants as well as the interface to the lawn. If the front edge looks great, other imperfections farther back are easily overlooked."
Moore prefers a natural spaded edge over plastic or metal. "This is especially true when plastic and metal heave out of the ground and become a crooked mess," she said. This typically happens during the freeze-and-thaw cycles that take place in northern climates.
Garden designer Kim Kaulas of Chicago often uses a spaded edge as well. "It's unobtrusive, and the plants remain the star of the show," Kaulas said. "However, with projects where I'm edging loose material like gravel, I like to use metal because it's also unobtrusive, and it seems to stay put pretty well, not heaving up over time."
For homeowners doing their own edging, place the spade perpendicular to the soil, slice straight down or on a slight angle and move the soil and any bits of grass onto the border. You'll want to break up those clods of soil and remove the grass and roots to the compost pile. A few times during the growing season, the edge can be trimmed with a mower or weed whacker to keep that crisp line.
Landscaper Steve Ruppert of Borden Landscaping in the south Chicago suburbs says that homeowners who dig a straight edge along their beds and borders should consider using (wood) mulch on the beds. "If you put down rock, it will get into the lawn." If you prefer using small landscaping stones for mulch, then wood, metal or flagstone would be a better edging material to keep the stones from rolling into the lawn. Much of Ruppert's landscape work involves natural edging, but flagstone and bull-nosed or interlocking cement pavers are also popular with his clients.
"Homeowners can often do stone or brick edging themselves if they're handy," Ruppert said, "but if you have curving natural lines, the bricks will need to be cut so they fit together properly." If your beds don't have straight lines, you may want to consider hiring a professional to install the edging. "Putting down a run of bricks is a bit tricky because you want them to be level so the mower can run over them, and it takes skill to fit them together so you don't get weeds coming up in between them."
For do-it-yourselfers, Kaulas also has some cautions. "A lot of homeowners think that adding a brick or stone border will contain the grass, but it won't," she said. They will need a proper limestone base, she said. Otherwise the bricks and stones that are set on the soil will eventually shift. "And the grass gradually creeps in under or around the stone, and the edging will have to be redone."
Another consideration is how much sun the area receives. "If the garden is shaded, and the adjoining lawn is spotty, a spaded edge does not work to make a sharp line," Moore said. "In those cases I use stone or pavers to delineate the edge."
For do-it-yourselfers purchasing from big-box stores, expect to spend about $1.25 to $1.50 for a 12-inch-long bull-nosed cement brick edger or a tumbled Belgian edger. Rubber edging costs $5 to $10 for a 4-foot-long section. A 24-foot section of aluminum edging is $40 to $50. Ground limestone or paver base, used as a foundation under bricks and flagstone, costs $3 to $4 a bag.
Horticulturist Susy Stone, of Naperville, Ill., has another idea. "I really do not use edging in my gardens . . . because I have always been changing and enlarging the beds," Stone said.
Spoken like a true gardener.