How to choose plants for your water garden

There are many different types of plants you can add to your water garden. Follow these suggestions to add some natural beauty to your man-made water feature.

• A man-made pool looks more natural with some shallow-water plants, such as cattails and flowering rush, growing around the edges
• Pools can be designed with shelves to give these plants the five to eight centimetres (two to three inches) of water they need over their roots, or, failing that, the containers holding them can be raised on bricks

• Plants such as the bog arum (Calla palustris), with creeping rhizomatous roots, should be planted in containers large enough to accommodate the rootstocks
• First, remove dead leaves and old brown roots
• Then place the rhizome horizontally on the soil, and use your fingers to pack the soil firmly, but not too tightly, around the roots
• Leave the rhizome itself exposed
• Cover the surface of the soil with coarse sand or pea gravel, and sink the container just deep enough so that the roots are completely covered by five to eight centimetres (two to three inches) of water

• In the case of shallow-water plants with tuberous root systems, such as the pickerel weed (Pontederia cordata), begin by removing all dead or discoloured leaves
• Then trim back any large shoots with a sharp knife
• Remove all of the old brown roots, and trim the remaining roots to a length of about eight centimetres
• Make a hole in the soil just deep enough to insert the plant, with the roots going straight down and the soil rising to the base of the shoots
• Pack the soil firmly around the plant, add coarse sand or pea gravel to the surface, and immerse it to a depth of five to eight centimetres (two to three inches)

• Oxygenating plants are essential in any water garden
• They maintain an ecological balance by using up the carbon dioxide produced by fish and other animals and by giving off oxygen that these animals require
• They provide fish with shelter and spawning places, and by competing with algae in the pool for light and nourishment, they help keep the water clear and fresh
• They perform the useful function of masking the water lily container
• Most of these plants, such as the anacharis (Elodea canadensis) and the cabomba (Cabomba caroliniana), are sold in the form of bunches of unrooted cuttings
• Their root-stocks develop quickly, so they need only be weighted down with lead sinkers, such as those used by fishermen, and dropped into pools with soil-covered bottoms
• Oxygenating plants can also be placed in containers of their own and then installed in the pool

• Some plants, such as the water lettuce (Pistia stratiotes), float on the surface of the pool
• Their trailing roots absorb dissolved nutrients that have come from the soil in containers of other plants or from fish droppings
• They are planted simply by putting them into the pool
• Some floating plants, such as the duckweed (Lemna minor), water hyacinth (Eichhornia), and azolla (Azolla caroliniana), proliferate so quickly that they may cover the surface of the pool
• Scoop out extra plants and compost them

By choosing the right plants for your water garden you can create a centrepiece of natural beauty you'll love.