native plantings and rain gardens--a natural landscape
this is a description of a landscape installation for a house I designed in Silver Spring, MD. it's written by the client, Janet Kinzer.
-AA
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Because of the scale of the gardens and the nearness of Sligo Creek it was important to landscape and garden Park Crest responsibly. We wanted native plants that would require little or no applications of fertilizers and insecticides, some of which would inevitably end up in the beautiful creek downhill of the gardens. We were also mindful of the enormous amount of water required to establish new plantings. The rain gardens help to maximize the use of rain water and, at the same time, minimize run-off to the creek.
The rain gardens are deeply dug pits holding layers of gravel and rocks which are then covered by a planting beds. Simply put they are all downhill of the down spouts, but uphill of the bed. Paul Crumrine situated the rain gardens very carefully, taking into account the down spouts, the aesthetic location of beds, and the terrain that suited the storage of water.
The gardens at Park Crest are all new and newly-planted. Instead of the daily and weekly regimen of watering for new plants, our gardens got most of their water from rain falling on the roof. The down spouts, which have been diverted and enhanced with buried extenders, collect enormous amounts of rain water from Park Crest's ample roof. The down spouts with their extenders, feed directly into the pits of gravel and rock, where it can filtered and distributed along the entire bed. Rain water can even be collected and stored by some of the rocky pits.
The prettiest rain garden, and the one that is probably most prominent in the pictures of Park Crest, is the one across the front porch. It is fed from the rain that rolls into the gutters along the western part of Park Crest's huge roof-line. That rain water is diverted into rocks that are along the back of a raised flower bed. This rain garden, because it is largely flat, can actually hold and store water. That bed holds a bank of bushes, fronted by grasses and flowering plants that are all perennials and native to the meadows of the mid-Atlantic states. We wanted this garden, because of its prominence, to be attractive all year long, and to take full advantage of the wide-variety of native plants available through Paul's network of environmentally-conscious nurseries.
The largest, and most important rain garden takes advantage of the rain water collected on the south-western portions of the roof. That part of the property, which we determined to be a "critical slope", held a number of mature, but diseased Tulip Poplars that had to be removed. The new plantings would have three important purposes: secure the slope, give the birds a protective and nourishing thicket, and eventually, screen the view of our neighbor to the south.
The drainpipe comes down near the kitchen bay and then passes under the southern stairs and pops out at top of that natural culvert that fills the southern side-yard of the property, about 15 feet wide by 70 feet long. Because this rain garden runs down-hill it purpose is to distribute rain water the full length of the garden. It feeds a bay magnolia, a dog wood and some other trees that survived construction, a host of ground cover plantings (to secure the slope) and berry-covered plants and shrubs that will lure the birds that inhabit the park.
-Janet Kinzer