Hi Linda, we've used them to outline a garden path. You can peek at it here if you like: https://www.exquisitelyunremarkable.com/2017/07/how-to-create-cottage-style-garden.html
Linda...I used mine under an old 150 plus year old pot my grandparents used to render lard durning hog killings. I have it hanging from to vinyl fence posts with a post at top and chains with planted flowers. It was difficult to weed eat under and we had removed some stepping stones redoing landscaping so decided to finish it with left over stones. I really like the look! Maybe this will give you an idea or two!
depending on how big they are, turn on edge and bury 1/2 way in the soil to create a border --- or carefully take a brick chisel and cut to a manageable size -- 1/2 or 1/3 would work
Instead og a border, we made stations for furniture. An entranceway to our gate and my glider chair, some under the adult swing set, and some as a walkway to connect the 2.