RENEGADE GARDENER™ The lone voice of horticultural reason Don't install plastic landscape edging improperly. Magnificent commercial installation: black plastic, pink rock, edging set too high Such a simple, helpful product, yet so easy to screw up. First off, a few notes: some gardeners don't like to edge their beds with plastic edging, having found that when they want to expand or change a bed, well, there's the edging to deal with. Edging keeps lawn grass from invading the garden beds, but ...