Landscaping for a Healthy Sound

From the crest of the Cascades to the crest of the Olympics, from north of Bellingham to south of Olympia, most of rain that falls on our homes, lawns, and driveways eventually finds its way into Puget Sound. What we do with and on our land directly affects the quality of our waters.

Thoughtful landscaping can change the volume, velocity, and timing of surface runoff that flows from) our property. Decreased volume decreases the danger of flooding, soil erosion, stream scouring, and the delivery of excessive sediment to the Sound.

  Getting Started

Planting   Trees, shrubs, and groundcover help reduce runoff, minimize erosion, and enhance the appearance and value of your property. Think about reducing your lawn and bare areas by increasing the number and variety of shrubs and trees.

If you build a new home, leave as much of the original vegetation as possible. Leaving the vegetation not only reduces runoff and pollution but gives you a head-start on your final landscaping and may increase the value of your home. It is particularly important to leave a vegetation buffer along streambanks and shorelines to avoid excessive runoff and erosion. Before you start construction grading, get a copy of the Associated General Contractors booklet, Waste Disposal and Erosion, and Sediment Control Methods, by calling (206) 284-0061. Read the booklet and share it with your builder.

Well planned landscaping has other benefits too. Planting choices and locations can reduce heating and cooling costs for your house by as much as 30%. Trees, shrubs, and groundcover require less maintenance than grass. They also require less fertilizer and fewer pesticides than grass, reducing the chances of your yard adding polluting runoff to the Sound. New shrubs and trees may also attract birds and wildlife.

Appropriate Plants for Puget Sound Landscapes Before you head for the nursery or garden shop, consider the growing conditions around your land. Fond of roses? Many varieties are susceptible to mildew and fungus. To keep these roses growing, Northwest gardeners often resort to heavy doses of pesticides.

   How To Choose…

Fortunately, nature has given us a hint. Over time, plants native to a particular locale have adapted to local growing conditions. Plants that grow naturally in the forests and open lands of the Puget Sound basin are well suited to our patterns of rainfall and are bothered less by common disease and insect problems than most plants introduced from other areas. So, as a first step in plant selection, look for native species.

Next, call the Washington Toxics Coalition at (206) 632-1545 and request Appropriate Plants for Northwest Landscapes. This fact sheet lists and describes appropriate groundcovers, shrubs, and trees. As a bonus, over three dozen disease resistant rhododendron types are listed, along with a list of inappropriate plants for Puget Sound landscapes. WSU Cooperative Extension has additional, helpful publications. Finally, ask a competent, professional nursery to help you select groundcovers, shrubs, and trees appropriate for your yard and soil type.

Other garden materials can influence runoff too. Avoid landscaping plastic beneath decorative rock or bark. The plastic prevents water from entering the soil. New, woven materials accomplish the task of weed control while permitting water penetration. Similarly, the chapter on erosion control discusses alternative, permeable paving surfaces for paths, walks, patios, and driveways.