Four-inch edging is not suitable for…
Four-inch edging is not suitable for soil with any type of resistance, such as due to rocks or clay content. Trying to tap the edging in place per directions was not possible, as the edging flexed and distorted. My purpose for the edging was to use as a border for a gravel pathway.
For my installation, I was required to dig a shallow trench, place the edging (leaving approx. 1 - 1.5 in above ground surface) and then backfill and tamp to hold each piece in place. Because of the looseness of this installation, I also drove 10 in. galvanized nails adjacent to the inside of the edging and secured with bailing wire to provide a firmer placement. Two holes were drilled in the edging next to each nail to allow the wire to be looped through the edging and back around the nail. The wire was then twisted to provide a firm attachment. Up to four nails per piece were required, with >2 for curved pieces. The head of each nail was ground to allow for a flat side to be adjacent to the edging.
I found the edging connectors to be of limited use as they also deflected in the clay and therefore did not align flat with the edging.