Filtering Grey Water: Species of Wetland Plants
Cattail, bulrush, reed and sedge species are all common in constructed wetland ecosystems, and each plays a specific role: Some remove heavy metals, while others are more skilled at removing organic matter.
Phragmites australis, the common reed, is often used in water treatment in Europe to remove nitrogen, but it can be invasive in North America and Australia.
Duckweed (Lemnoideae family) also removes nitrogen and phosphorus.
Typha has shown promise for removing heavy metals, and for those who weave, its vegetation can be used for mats and baskets.
Iris and water hyacinth can also remove heavy metals such as lead, copper, zinc, nickel and cadmium.
Greening Your Grey Water
As with all choices of wetland plants for the garden, reed species should be chosen with the local ecology in mind. Always check with local wetland plant experts to ensure that a species is not invasive in your local wetlands. since many wetland species breed and spread easily!
A wetland garden can be full of life. It can also add to the sustainability of a home by allowing a gardener to conserve and reuse grey water. So don’t let all that water just do down the drain – turn a pond or a wet garden into a place that works for the planet by reframing it as a water treatment system.
US Army Corps of Engineers. The National Wetland Plant List. (2012). Accessed January 11, 2012.
Echolumina. Constructed Wetlands. (2007). Accessed January 11, 2013.
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