A flat-tipped shovel can be used to cut a trench for maintaining the garden's edge.

Natural Garden Trench Edging

by Brian Barth

Garden edging is underrated. Though the term can refer to physical pieces of edging -- wood, plastic, metal, concrete, brick or stone borders that delineate the perimeter of a planting area -- as a verb, "edging" refers to the act of making the border by hand in the soil, such as by digging a trench. This natural approach to edging saves money and does not use unsustainable resources.

Purpose of Edging

Edging is one of the secrets to a well-kept garden. It's purpose is to make distinct transitions between areas of the landscape, such as the border between a lawn and a flower bed. You may not notice edging if you're not looking for it, but it's hard not to appreciate the crisp, clean feel that it provides. On a practical note, edging prevents creeping lawns grasses and other aggressive plants from taking over nearby plantings.

The Necessary Tools

At a minimum you will need a shovel -- the sharper the blade, the better for edging around a thick mat of sod. As you may have guessed, there are special tools called edging shovels that make the work easier. The blade comes presharpened and is completely flat, unlike a "flat shovel" which actually has a slight angle. You'll also want a wheelbarrow or garden cart ready to haul away the chunks of sod and a pair of gloves to protect your hands from any soil-borne pathogens that may be present.

A Straightforward Technique

Slice vertically into the soil with your shovel of choice along the line where you want to define the edge. If edging a lawn, stand in the lawn facing the adjacent bed and pry up on the sod with each slice. The goal is to form a trench 4 to 6 inches deep between the two planting areas. An edging shovel isn't good for scooping up the chunks of soil and sod, so have a regular shovel handy, as well. After you make one pass, go back and clean it up to make a smooth, crisp line. A trenching shovel is useful for scooping the dirt out of the trench after you've loosened it.

Edge Maintenance

The point of edging is to prevent plants from growing beyond it. A few weeks after you cut a nice, clean edge in a lawn, you'll notice the grass is starting to grow into the trench. Before long, it will invade the neighboring soil and you'll have to repeat the process. For some slow-growing grasses, two or three edgings a year is generally sufficient, while others may need it monthly during the growing season. You may want to place a few rocks along the edge of the trench or mark it some other way, such as with solar lights so that unsuspecting visitors or busy children don't hurt themselves.

About the Author

Brian Barth works in the fields of landscape architecture and urban planning and is co-founder of Urban Agriculture, Inc., an Atlanta-based design firm where he is head environmental consultant. He holds a Master's Degree in Environmental Planning and Design from the University of Georgia. His blog, Food for Thought, explores the themes of land use, urban agriculture, and environmental literacy.

Photo Credits

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