Plastic Edging for Rocks

Low Fills

• Black plastic edging that is sold in rolls of 40 to 60 feet or more is the cheapest edging available in retail garden centers. It may be all that is required to outline a bed or pathway that is filled with pea-sized rocks or gravel. This style of edging allows rounded curves for a more fluid appearance. It presents a finished profile of less than an inch in height and is adequate for retention of small rocks.

Tall Edges

• Beds filled with larger stones, such as lava rock and marble chips, require edging tall enough to contain the formations desired. Tall, flat edging provides a back-board to guide string trimmer operation, where beds adjoin the lawn. Crisp edges are formed and maintained easily. Different types and styles are available in several sizes, designed for differing needs. Select edging that will yield a finished height of at least 3 inches to better retain rocks or gravel.

Straight Designs

• Some plastic edging is made of flexible panels, 2 feet in length, that interlock to form straight lines. Gradual curves can be attained, but no means are provided for shaping right angles. The best use of this tall plastic edging is to enclose a niche, or any shallow architectural recess. This edging is commonly available in green or black, and stands approximately 3 1/2 inches tall after the scalloped side is driven into the soil.

Square Beds and Angles

• Molded plastic edging kits have 16 inch long panels that interlock to form straight lines, but also come equipped with corner braces. The braces interlock with the panels to allow right angle turns, and can form square or rectangular beds. The rigid panels have grey or beige faux-rock finish, and have a height of about 3 inches after installation. The sharpened side of the rigid plastic is easily driven into loose soil.