I am redoing my pond and I really want to have a very shallow ledge around the edge for planting marginals. I don't want them to be in pots just planted directed into some sand or gravel around the edges. I was thinking of about 5-6 inches deep but I saw somewhere that 10-12 inches of water was best for marginals. I really want the edges to look like a natural pond where the water just laps up to the rocks and plants are growing along the bank.
Is this going to be too shallow to plant marginals in? I'll have a shelf further in that will be about 10-12 inches deep but I'm not going to want to see the line for 12 inches all around the pond.