I want to build a wildlife pond like the one Joel Ashton shows in his YouTube videos. He stipulates subsoil should be used as the substrate for planting wild flowers around the edges and in the pond itself. Although there are many outlets for topsoil, there are very few that will supply subsoil. The subsoil must have a low nutrient level and only have 2% organic matter. Joel has supplied me with three suppliers , but they are all far from me in the south of England. I know that we all have subsoil under our topsoil, but it looks as if Joel uses quite a lot when he builds the pond and I don't think I could dig out that amount in a reasonable amount of time.I know that I can use gravel and stones as well, but still need quite a lot of subsoil on top of the stones. Does anyone know of a supplier in the East of England?