Let Loose on Low Wet Areas
When dealing with consistently or frequently wet soils in low areas, remember that pooling water is an indication of poor drainage and low infiltration rates into the soil. It is, therefore, not the ideal site for a rain garden. This situation is, however, a perfect opportunity for plantings of native moisture-loving plants to create a functional solution to an otherwise problematic site.
There are many attractive native wetland plant species that thrive in poorly drained, wet soils. Many of these are the same species used for planting rain gardens and bioswales. A list of plant species for wet soils is useful when designing a garden for this situation. (See Select Plants.)
Native suckering sedges can be used to create low maintenance landscapes where there are poorly drained and/or clayey soils in your yard. They need an edge such as mowed lawn, concrete curbing or a building to contain growth. Gold sedge (Carex aureolensis) at 18 inches is a good choice for shade; creeping quickly fills into a solid mat. It will fill in during a single growing season, greatly reducing weeds and the need to mulch. Simply mow in March and remove occasional weeds throughout the growing season. Brown bog sedge (Carex buxbaumii), riverbank sedge (Carex emoryi), tussock sedge (Carex stricta) and wool sedge (Carex lanuginose) are other top-performing low-maintenance groundcovers for wet soils.
You can choose to dig a basin in a low wet area in your yard to create a small pond. If you install a pond in your yard, consider submerged plants you can include in your pond, and plants for moist soils for the area surrounding the pond.