I recently dig a pond in my back garden, with a ledge around the side especially for the plants. I tried the plants for size and stability before I added the water and they were fine. However when I transported the water (from the old pond with no ledge to the new pond) the plants wouldn't stand up. The plants a quite tall, around 3 feet high some of them. I have tried balancing rocks on the plant pots under the water it didn't work. I also tried putting rocks in the bottom of the pots but this still didn't work, I think because of the weight and height of the plants. Unfortunately the ledge around the side isn't very wide, (only just wide enough for the plants) and neither is it as straight as I had originally thought or intended, but it is ALMOST Straight. What I'm asking is what can I do to make such tall plants stay standing up, without putting them in the middle of the pond at its deepest? Thanks in advance for all answers. Not sure if this makes a difference due to the health and safety code of pond life lol, but I do have fish, toads and a newt already in there, so answers which could hurt them wouldn't be so great, but thanks.