With the proper plants, even a backyard marsh can bring an enchanting dimension to your landscape. A marsh garden's surface reflects the sky, trees and blooming plants above, multiplying the beauty of its surroundings. The native marsh shrubs in your area will be reliable additions to your garden, providing spring and summer bloom and fall foliage. They'll also shelter and--in some cases--feed wildlife.
Swamp azalea (Rhododendron viscosum) grows wild in marshes and bogs from Florida as far north as Vermont and west to Oklahoma. Standing up to 5 feet high and 12 feet wide, it has a loose airy habit with 1.5-to-3.5-inch glossy green leaves clustered at the ends of its branches. Fragrant white flowers appear after the leaves, any time between May and August.
Their blooming season makes these azaleas good choices for gardeners who want to extend the azalea flowering season. Five-petaled white blooms have pale purple bases and yellow stamens. The shrub's orange or maroon fall foliage adds further garden interest. Plant swamp azalea in part shade and moist, well-drained acidic soil. Like all members of the rhododendron family, swamp azalea is toxic to both humans and animals. All of its parts may be fatal if ingested.
Scarlet Rose Mallow
Scarlet rose-mallow (Hibiscus coccineus), says the Lady Bird Johnson Wildflower Center, is among the loveliest of America's native plants. Found along the marshes and swamps of the southern United States north to Virginia and Arkansas, this medium-sized shrub stands between 4 and 7 feet high with a spread of 2 to 3 feet. Its stature makes scarlet rose mallow's 6-inch wide brilliant summer blooms even more showy. The flowers' stamens match their five crimson petals.
Scarlet rose mallow leafs out late in spring and blooms between July and September. It likes full sun and tolerates high summer temperatures and humidity, and requires wet soil. The Missouri Botanical Garden recommends scarlet rose mallow for the rear of perennial borders as well as a water garden plant.
Also called sheep laurel, lambkill kalmia (Kalmia angustifolia) belongs to the heath family. Growing up to 3 feet high and 6 feet wide, lambkill kalmia is an evergreen shrub found wild along swamps, bogs and stream banks and in pastures and thickets from the U.S. mid-Atlantic states north through New England into Canada.
The shrub's trailing stems have upright tips and form heavy mats of glossy bluish-green elliptical leaves that take on a reddish tone in autumn. Its purple or red bell-shaped flowers appear in clusters beneath the leaves between June and July. Lambkill kalmia colonizes readily, making a good cover for wet areas where little else will grow.
This shrub favors partly shady locations with wet, slightly acidic rich soil but will survive dry infertile conditions. It may develop iron deficiency in high-limestone soil. Deadheading it (pinching spent flowers off between your thumb and forefinger) will encourage more abundant bloom the next year.