It was just uploaded by david potter, another amazing video “Growing Supermarket Water Cress in Garden Pond hack”.
As informed in the youtube page by david potter: “There will be people out there saying it’s not right or it could pollute the pond etc, but I say it works with me and as long as you keep the pond fresh, it will spread and come up every year. It’s also good cover for the private weather loach and carp and it produces nice white flowers. The long and the short of it is that it costs £1.30 and we had over half the packet in our lunchtime salad. DO NOT eat the watercress after it’s gone in the pond. It may have harmful parasites unlike the supermarket packet which has been carefully washed at the factory in spring water etc.”
You can check the video below: