Garden Talk: Planting options for sites with moisture
Dry times and drought-tolerant plants have been at the forefront of our attention this year. However, there are still homeowners who have some areas that are typically a bit wetter than average, particularly around ponds or other bodies of water. For those areas, plant recommendations are naturally quite different from the best choices for dry spots.
A number of trees do very well in moist areas. Each offers its own strengths and weaknesses. The river birch, a native found in flood plains, is a perfect example of the blend. It offers particularly attractive bark but is fussy about soil ph, requiring 6.0-6.5, quite an acid soil. It also presents maintenance issues with many twigs that come down from storms.
The silver maple is an adaptable tree offering quick growth. However, its wood is weak, and it should not be used as a street tree or shade tree. The black alder is another quick grower and provides shiny dark green foliage. American hornbeams are small, tough, and durable, and the American larch provides the option of a deciduous conifer.
Sweetgum, a tree reaching 50-60 feet at maturity, offers dark, shiny leaves in summer and excellent fall foliage. It does present maintenance issues with spiny fruits that drop in fall, but seedless varieties are available. The black gum, known also as sour gum, also offers terrific fall foliage. It likes acid soil and has a significant taproot, making transplantation difficult.
If you are thinking big for a moist site, consider the sycamore, a native tree with huge leaves and interesting peeling bark. It makes a very attractive winter tree. However, sycamores are susceptible to anthracnose and present a maintenance problem with small branches dropping.
Another especially attractive option is the bald cypress, a deciduous conifer. Its fine-textured foliage is very pleasing. Finally, the pin oak offers quick growth, easy transplantation, and wine red fall foliage. It prefers an acid soil. Because its lower limbs droop, it is not a good street tree.
Turning to shrubs, two natives head the list. Wet chokeberry offers very attractive foliage, flowers, and berries. Buttonbush is an outstanding selection for marshy areas.
Red osier dogwood is another very hardy native.
Other good shrubs include summersweet, Virginia sweetspire, and arrowwood viburnum. Hollies are good for acid soil but require the planting of at least one male. Northern bayberry is an exceptionally adaptable shrub with leathery dark leaves.
Perennials that thrive in wet areas include jack in the pulpit, cardinal flower, Solomon’s seal, swamp milkweed, and ferns, all best in natural areas. Others that can be incorporated into perennial borders with good water sources include turtlehead, Joe Pye weed, hardy hibiscus, Siberian iris, and spiderwort.