Soil placed in ornamental ponds or for container-grow aquatic plants must be dense and heavy. Making pond soil requires a clean, dense topsoil that's rich in clay. Using well-composted cow manure adds nutrients and an improved texture to soils used in submerged containers.
Search your yard for clay-based soil that has little organic matter in it. Purchase topsoil in bags, if necessary, from a garden center. The heavier and denser the soil, the better.
Put three parts topsoil into a wheelbarrow. Pick out organic matter such as bark or leaf compost that will float in the pond once the soil is submerged.
Add one part well-rotted cow manure to the topsoil. Thoroughly combine the contents of the wheelbarrow with the shovel so there is a consistent blend and texture.
Add water to the mixture if it is overly dry and you cannot judge its density. Slowly add water and mix so you don't inadvertently make the soil into a soupy mess of mud. You want it to be sticky, like warm cookie dough.
Things You Will Need
- Dense topsoil
- Decomposed cow manure
- Addition of the well-rotted cow manure is optional, but recommended if the soil is to sustain robust plant growth. Clay soils are ideal for use in ponds and submersed plant pots, and dense loams are acceptable as long as organic material is minimal or absent.
- Do not use potting mixes for pond soil, as they contain perlite, compost, fertilizer granules and vermiculite that will float in the pond water.
- Avoid gathering topsoil from woodland areas, as it will be ridden with organic matter, such as leaves and twigs.
- Avoid sandy soils, as they are not dense and can release debris and particles quickly to cloudy pond water. In addition, water plant roots will not readily grasp into sand and may float up to the surface.