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Choose plants native to your area. Purchase perennial plants that have already matured. Look for plants that thrive well in wetlands. Add shrubs for erosion protection.
Plants that thrive well in rain gardens are hardy and healthy. Your rain garden will be most low-maintenance with regional plants because they will be adapted to the climate and local rainfall fluctuations. The best place to purchase native plants is at locally-owned plant nurseries. Younger plants will not thrive as well with high quantities of waters, so avoid buying seeds or seedlings. Their root systems are not developed enough to handle the downpour. Perennial plants last for several years, so plants at least one or two years old will have established root systems. Ask your local nursery for specifically mature plants to avoid receiving seedlings. Choose plants that can handle lots of downpour. You can find native wetland plants via the U.S. Army Corps of Engineers National Wetland Plant List (NWPL) by visiting: http://wetland-plants.usace.army.mil/nwpl_static/index.html. You can also check local gardening magazines or your city's plant nursery to ask which wetland plants thrive in your climate. Plants with dense root systems hold rain gardens together best. Shrubs generally have developed root systems that soak up excess water and prevent land erosion. Look for shrubs best adapted to your soil conditions. Most shrubs prefer well-draining soil to clays. Shrubs grow best in moist but not oversaturated conditions. Add several shrubs to rain gardens with especially excessive runoffs.