How to Create a Mini-Wetland
By doing so, you'll help provide habitat for a host of creatures—from butterflies and bees to salamanders, toads, frogs and birds
Once dismissed as breeding grounds of disease, many of our nation´s swamps, bogs and wet meadows have been drained and filled. "We have lost more than 50 percent of our native wetlands in the lower 48 states since colonial times," says Doug Inkley, a wetlands specialist and senior staff scientist at the National Wildlife Federation. "It wasn´t until quite recently that researchers realized what a vital role wetlands play in the nation´s ecosystems."
Not only do wetlands provide feeding and breeding grounds for millions of shorebirds and waterfowl, they also sustain great numbers of endangered and threatened species of wildlife. In addition, wetlands are natural filters, removing pollution and other impurities from water supplies.
Because of their importance, many damaged wetlands are now being restored. And with a little effort, you can create a mini-wetland in your own yard. By doing so, you´ll be helping to provide habitat for a host of creatures--from butterflies and bees to salamanders, toads, frogs and birds.
If done properly, a mini-wetland can be an attractive focal point for your backyard landscape. One way to achieve this is to create a dry stream bed flanked by wetland areas. Dig two hollows on each side of a three-foot-wide strip. Cover the entire area with plastic and arrange stones of varying sizes down the center strip. Place three or more ground-level bird baths among the stones to mimic small pools.
Where garden space is limited, a long narrow trench excavated between property lines can be planted to imitate a roadside ditch. Such a small swampy habitat will play an important role by creating food, shelter, protective edges and travel routes for small wildlife in suburban developments.
The easiest sites to establish as wetlands are those that remain naturally wet or damp throughout the year. Such sites include depressions that collect rainwater or receive runoff from downspouts and the marshy edges of a pond or stream. A wetland created as an extension to a pond will also provide a microenvironment for the creatures that dwell and feed around the pond´s watery edges. Creating a wetland garden is very simple even when there are no natural wet spots. If possible, however, choose a site in partial shade or plant a few shrubs and trees on the fringes of the wetland.
Begin by outlining the shape with twine or a garden hose. Scoop off the sod and dig a one-foot-deep hollow. (To accommodate trees and large shrubs on the fringes, dig the holes at least two feet deep.) Line the hollowed area with plastic. If you live in a region with heavy annual rainfall, puncture the liner in several places to create slow drainage. If your site is naturally and constantly moist, it will not require lining with plastic except in a small area where you may want to create a tiny pool.
Fill the plastic-lined hollow with two inches of pebbles, followed by two-inch layers of peat moss, coarse builders´ sand and roughly chopped sod. Top with the removed soil and enrich with composted materials, shredded leaves or more chopped sod.
There are several ways to keep your artificial wetland garden moist. It can be fed by a fountain spout connected to a recirculating pump immersed in a small pool, or by a fountain spout attached to a garden hose. Sink the hose one inch or so into the ground to protect it from the lawnmower. Or you can bury a perforated soaker hose two to three inches below the soil level.
Now you´re ready to plant. Fortunately, you have plenty of choices: Many plant species are specially adapted to growth in wet soils. "A shallow pond and wetland planted with cattails and reeds will attract frogs and other small creatures that hibernate in mud through the winter," says Inkley. "You can also grow some really beautiful plants such as pitcher plants and pink lady slippers."
Ferns are also wetland naturals. Royal, ostrich and cinnamon ferns grow five to six feet tall. Not only do the delicate fronds of these tall ferns add elements of grace and beauty to a wetland, they also provide hiding places for small creatures including tree frogs, salamanders, toads and snakes. Wetland wildflowers can provide nectar, pollen and seeds for insects and birds, as well as a succession of beautiful blooms for people to enjoy. Flowers that fill such dual roles include marsh marigold, true forget-me-nots, cardinal flowers, great lobelia, yellow coneflower, bee balm, swamp milkweed, Joe-Pye-weed, lance-leaved goldenrod and New England aster. And, of course, there are several native orchids that love boggy conditions. These include rose pogonia and grass pink, both of which produce delicate blossoms.
Some trees and shrubs, such as birch, red-osier dogwood, sweet gum, nannyberry and mountain laurel, provide not only food and shelter but add texture and color to the landscape during the bleaker months. Swamp maple, with its red stems and red leaves, adds an ornamental touch in the fall in some areas. In southern areas, sweet gum makes a beautiful addition to a wetland. If you live in the north, try tamarack. Inkley also recommends planting blueberries and cranberries. "Besides thriving in very wet areas and providing abundant food for wildlife," he says, "they are also colorful in the fall."
When choosing plants for your new backyard habitat, don´t go shopping in existing wetlands, Inkley cautions. "While it may be tempting to collect native wetland species from the wild, there are laws against it in some areas and you could disrupt the wetland," he says. "You need to go to a reputable nursery to ensure the plants have been commercially propagated, not collected."
For more information, write Backyard Wildlife Habitat™ program, NWF, 11100 Wildlife Center Drive, Reston VA, 20190.
Find out how you can turn your garden into a Certified Wildlife Habitat.