Flower bed edging is the process of creating a clean, defined border between a planting area and the surrounding lawn, path, or patio. This simple landscaping technique instantly elevates the appearance of any garden space, lending a polished and organized look to the entire yard. Edging establishes a clear boundary, which is the foundational step toward a well-maintained and aesthetically pleasing flower bed.
The Function of Flower Bed Edging
The primary practical function of edging is to act as a root and growth barrier, preventing turfgrass from encroaching into the cultivated soil of the flower bed. Aggressive grasses, such as Bermuda or Zoysia, send out rhizomes and stolons that quickly invade planting areas, competing with ornamental plants for water and nutrients. A physical or trench barrier disrupts this horizontal growth pattern, keeping the grass contained in the lawn area.
Edging also plays an important role in material containment, ensuring that mulches, decorative gravel, or soil amendments remain within the bed boundaries. Without a defined edge, these materials are easily displaced by rainfall, wind, or routine garden activity, leading to loss and a messy appearance. Furthermore, a clean border simplifies maintenance by providing a straight line to follow when mowing or string trimming the lawn. This separation protects plants from accidental damage by yard equipment.
Selecting the Best Edging Material
The choice of edging material significantly impacts the durability, cost, and overall aesthetic of the finished garden border.
Metal Edging
Metal edging, typically made from steel or aluminum, offers superior longevity and a sleek, modern appearance. This material is highly durable, resists damage and can be bent to accommodate gentle curves, making it a long-term investment. However, metal options generally have a higher initial cost.
Plastic and Vinyl Edging
Plastic or vinyl edging is often the most budget-friendly option and provides maximum flexibility for intricate curves and shapes. While easy to install, lower-grade plastic can become brittle, crack, or warp over time, requiring eventual replacement.
Hardscape Materials
For a more permanent and natural look, materials like brick, stone, or pre-cast concrete offer a timeless aesthetic and exceptional durability. These options are the most expensive and labor-intensive to install due to the weight and the need to set them securely, often in a sand or concrete base.
Natural Trench Edging
An alternative to physical barriers is the natural, trench-cut edge, which uses a specialized spade to create a sharp, angled V-cut between the lawn and the bed. This method costs nothing for materials and allows for easy bed shape changes, but it requires annual or semi-annual re-cutting to maintain the sharp definition against root encroachment. The technique relies on a vertical cut of four to six inches deep to physically sever the grass roots.
Step-by-Step Guide to Installation
The process of installing a permanent edge begins with preparation and marking of the desired border shape.
1. Mark the Layout
Use a flexible garden hose or rope to lay out the line of the bed, allowing you to visualize the final curve before digging. Once satisfied with the layout, use marking paint or flour to trace the exact line on the ground.
2. Excavate the Trench
A trench must be excavated along this marked line using a flat spade or a half-moon edger tool. The trench should be cut four to six inches deep and slightly wider than the edging material to allow for easy placement and backfilling. For thin materials like plastic or metal, the depth should allow the top edge to stand about a half-inch above the soil line to prevent grass from growing over it. The removed soil and sod should be kept nearby for the backfilling stage.
3. Position the Edging
With the trench ready, the chosen material is carefully positioned within the channel, ensuring it follows the marked line precisely. Thin barrier materials like metal or commercial-grade plastic are joined with connectors and secured using anchoring stakes driven into the ground every three to five feet. For heavy materials like bricks or stone, the base of the trench may require a layer of compacted gravel or sand to provide a stable, level foundation before the units are set.
4. Backfill and Finish
The final step involves backfilling the trench by returning the excavated soil to both sides of the installed barrier. As the soil is added, firmly tamp it down to compact the earth against the edging material, which locks it into place and prevents shifting. The remaining area of the flower bed is then finished by spreading a layer of mulch right up to the new edge to suppress weeds and retain soil moisture.
Keeping Your Edges Sharp
Maintaining the clean appearance of a flower bed edge requires routine attention, especially for natural, trench-cut borders. For material barriers, regularly inspect the line for any sections that may have lifted out of the ground due to frost heave or soil movement. If sections have risen, they should be immediately tamped or hammered back down to the proper grade to prevent grass from growing over the top.
The area immediately adjacent to the edge must be trimmed periodically to prevent grass blades from leaning into the bed and softening the defined line. Using a string trimmer held vertically or hand shears to cut along the barrier helps maintain a sharp 90-degree angle. Natural, trenched edges should be re-cut with a spade or edger tool at least once annually, typically in the spring, to remove new root growth and restore the visual separation.