Flowers

Plants suitable for rain gardens, “Rain Garden Handbook for Western Washington”

Foodies get to drool over countless images online and in print of perfectly posed burgers, mouth-watering slices of pies, and other culinary treats. Now rain garden junkies and the bioretention-curious can indulge in inspiring photos and illustrations of green stormwater solutions in the newly released “Rain Garden Handbook for Western Washington: A Guide for Design, Installation, and Maintenance.”

The handbook is a step-by-step guide on how to plan, build, plant, and maintain a smaller-scale rain garden. It explains how even a modest-sized rain garden will capture and treat significant amounts of polluted runoff that flow off rooftops and driveways.

  • Suitable to an experienced landscaper or even a novice, the guide provides straightforward instructions in layman’s terms and lots of images to illustrate what’s being discussed. The handbook also answers questions and fears about rain gardens, including the persistent worry about standing water and mosquitoes (well-designed rain gardens drain in one to three days, the guide explains, and mosquitoes go from egg to adult in four or more days).

    Rain garden

    Cross section of a rain garden, “Rain Garden Handbook for Western Washington”

    The author, Curtis Hinman of Washington State University’s Puyallup stormwater center, takes pains to spell out exactly where rain gardens should and should not go (steep slopes, 10 feet from a building foundation, and directly above buried utilities are among the no-nos). He gives a variety of suggestions for designs of gardens, and concludes with an appendix featuring images and names of plants well suited to rain gardens.

    The handbook left me with the overall impression that a rain garden would be a bigger DIY project than I would want to take on by myself, though as the mom of a busy preschooler I’m less bold in that arena than I once was. But it offers a great blueprint for a community project, and it could be a useful tool for a homeowner working with an engineer or landscaper to help them better understand the mechanics of a rain garden. It would also be a terrific template for someone outside the Northwest who would like to create a guidebook tailored to their specific region.

    Salish map

    Salish Sea, “Health of the Salish Sea Ecosystem Report”

    Such a solid tool for expanding the use of rain gardens is most welcome and timely. Also this week, the US Environmental Protection Agency and Environment Canada released their “Health of the Salish Sea Ecosystem Report,” a report card on the waters of Puget Sound and some of the inland waters in British Columbia. The report scores “marine water quality” as being in decline, particularly in terms of low oxygen levels found in local marine waters.

    The EPA/Environment Canada study includes tips for residents and businesses eager to help recover the health of the Salish Sea. The No. 1 recommendation for improving water quality?

    “Use beneficial landscaping techniques such as rain gardens, rain barrels, green roofs and permeable paving to help reduce the need for chemical fertilizers and reduce runoff into ditches and storm drains.”