Whenever I am working to resolve water problems in a landscape, I must acknowledge that water will always win. The best we can do is creatively direct it toward the areas where we would like it to end up, with a focus on minimizing erosion damage and retaining as much water as possible for use on site. Plants can be part of the solution, and some erosion control systems even double as useful outdoor spaces like patios and walkways. Here are a few ideas to get you thinking about how you can manage rainwater in your own garden.
One of the simplest ways to manage rainwater in the landscape is with the thoughtful placement of planting beds. For example, plantings on steep slopes can be used to slow down water and prevent erosion. One of my favorite shrubs for this purpose is ‘Gro-Low’ sumac (Rhus aromatica ‘Gro-Low’ Zones 4–9). When installing a ground cover like ‘Gro-Low’ on a steep slope, you can provide additional erosion control by covering the bare ground between plants with a coconut-fiber mat. This biodegradable material will cover the ground effectively for several years until the plants grow together to form a continuous ground cover. Coconut-fiber mat is available in rolls at home improvement centers, farm supply stores, and from suppliers that carry stormwater-drainage systems and materials.
Another idea for planting on a slope is to combine plants with fibrous root systems that hold soil in place; these can be used in conjunction with plants that have abundant overhead branching or foliage to buffer rainfall from above. The best mixed plantings create appealing displays of color and texture and are very effective in controlling and absorbing rainwater. Most ornamental grasses have extensive root systems that are
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