Landscape edging separates, outlines --
Certain materials provide a more formal appearance than others


August 14, 2008


By Don Mader, Victoria County Master Gardener


Edited by Charla Borchers Leon, Victoria County Master Gardener

Photo Credit: Don Mader/Victoria County Master Gardener
Pre-cast edgers are available in a variety of shapes, surfaces, sizes and colors. These allow for attractive curves and the ability to lay a section now and add to it later.
Landscape edging is used to separate lawn from plantings or to outline various elements of the landscape like driveways and sidewalks. Materials for edging include plastic metal, wood, natural stone, pre-cast concrete edgers and poured concrete curbing.

Several points should be considered before buying anything for edging. Do you want a formal or informal look? Certain materials provide a more formal appearance than others.

If adding one or more beds, have you developed an overall landscape plan? Some of the available materials allow for modification of a design more readily than others if you change your mind.

Little or no maintenance of edging is needed if it is installed properly, including laying down a stable base first.

Last, but not least, how much do you want to invest? Some materials lend themselves more easily to laying a section now and adding to it later than others.

Many areas in and around Victoria have black clay or hardpan soil three or four inches below the topsoil. Amending a soil/clay or soil hardpan combination without causing a drainage problem is difficult at best. Most folks find it easier to make raised beds. A number of different edging materials lend themselves to this approach.

PLASTIC

PVC edging is very flexible, allowing for curved designs and easy installation. PVC edging comes in rolls in lengths of twenty to sixty feet and in several grades, from light weight to “professional.”

Prices range from approximately 37 to 70 cents or more a linear foot. Rolled edging should be almost completely buried as lateral pressure from soil in a raised bed will cause it to twist out of shape.

U-shaped wire stakes 10- to 12-inches long can be purchased to keep the roll in place. I make my own stakes out of wire coat hangers at no cost.

In my mind, PVC is most useful when butted up against paved driveways, sidewalks or curbs and installed an inch or two above the finished surface. This makes it easier to control the grass when using a string trimmer.
Vertical wooden post edging, with rubber backing and spikes for stability, can provide a curved outline in a landscape.
WOOD

All wood products should be either pressure treated or naturally resistant such as cedar. Pressure treated landscape timbers are readily available in eight foot lengths by 4 inch by 6 inch widths.

They are also inexpensive to install, averaging 50 cents per linear foot; a definite advantage if you have long straight runs. They are relatively long lasting and weather to a natural and attractive gray.

On the down side, termites are a fact of life in our area, especially since we seldom have long-lasting, hard freezes.

Other materials should be considered when using edging close to the foundations of your house.

Care must be taken to ensure a level bed the length of the run, as nothing is more apparent to the eye on longer runs than when the timbers are not level and even.

Timbers can be used for a low raised bed when they are overlapped at the corners like stacking a log cabin.

Engineering and construction techniques generally beyond the skills of the average homeowner or gardener are needed to go higher than 2 feet.

Layers of timbers in a raised bed need to be nailed or screwed together, as well as secured to the ground. The easiest method of doing this is to drill 1/2-inch holes in the layers at the end of each piece and drive 1/2 inch by 2 foot pieces of rebar through the holes and into the ground. Rebar pre-cut to this size is readily available at the big box stores.

A gradual curve can be made by using a miter saw to cut pieces 18- to 24-inches long and mitered at 20 degree angles. Miter the right angle corners at 45 degrees for a more finished effect.
A more natural edging is like these 4 by 8 inch stones mortared together by Master Gardener, Don Mader to form a raised bed in the landscape.
NATURAL STONE

Natural stone makes an attractive and informal edge. I’ve gathered stone roughly 4 to 8 inches in size when on vacation in various locations.

I mortared them together to make a unique, raised flower bed. Similar stones can be purchased locally by checking the yellow pages.
Some edges have a lip on the lower rear edge creating a stable stacking method.




Stacked tree rings can be creatively applied to an already existing raised bed to provide depth in a small garden.
PRE-CAST CONCRETE EDGERS, POURED CONCRETE

Pre-cast concrete creates a more formal look. These edgers are available in a variety of shapes, surfaces, sizes and colors, costing roughly a $1.50 to $3 per linear foot.

They are also heavy, weighing from 9 to more than 20 pounds a piece.

Most have mitered side edges, making it simple to create attractive curves.

Some have a raised lip on the bottom back edge, allowing them to be stacked with more stability.

Some have pre-etched grooves to easily break them in half using a masonry chisel and hammer.

Be sure to wear safety glasses when doing this. If using pre-cast edgers to make a raised bed more than two rows high, it’s recommended to first bury a course level with the ground to create a strong and secure base.

Again, two feet is the maximum safe height to build a raised bed or retaining wall. A poured concrete edge is the strongest, but it is permanent. It’s also the most expensive.

If using an informal look, try turning your creativity loose by using a variety of edging materials. For example, you can stack tree rings on top of an existing raised bed to create depth in a small landscaped area or use wooden post edging with rubber backing and spikes as stability to create a curved design.

Most of the materials I have mentioned are available in garden centers at large home product stores locally. A special thanks to Home Depot, Lowe’s and Wal-Mart for allowing me to photograph their products.

The Gardeners’ Dirt is edited by Charla Borchers Leon and is written by members of the Victoria County Master Gardener Association, an educational outreach of Texas Cooperative Extension-Victoria County. Mail your questions in care of the Advocate, P.O. Box 1518, Victoria, TX 77901; or vcmga@vicad.com, or comment on this column at www.VictoriaAdvocate.com.
LANDSCAPE EDGING MATERIALS

Plastic

Metal

Wood

Natural stone

Pre-cast stone edgers

Concrete

SELECTING EDGING MATERIALS

Purpose or desired effect

Formal or informal look

Match existing landscape

Ability to modify design

Straight or curved

Length and height

Establishment and maintenance

Amount of investment