Ask a Gardener: Best plants for wet locations
Question: I have a wet spot in my lawn where the grass is struggling. I would like to replace the grass with plants for birds and butterflies. What can I grow there?
Answer: There are a number of plants that will thrive in a sunny, soggy spot. To lure birds, butterflies and other native pollinators, I would suggest using natives (or near-natives).
Some shrubs for sun or light shade include summersweet (Clethra alnifolia), red-osier dogwood (Cornus stolonifera), buttonwood (Cephalanthus occidentalis), fringetree (Chionanthus virginicus), swamp rose (Rosa palustris), pussy willow (Salix discolor), red or black chokeberry (Aronia arbutifolia, A. melanocarpa), swamp azalea (Rhododendron viscosum), and winterberry (a deciduous holly, Ilex verticillata).
Note that winterberry, like all hollies, is dioecious. That means that both a male and female plant are needed for fruit to be produced on the female plant. If there's room for a small tree, try sweetbay magnolia, Magnolia virginiana.
Native perennials for a sunny soggy spot include swamp milkweed (Asclepias incarnata), beebalm (Monarda species), marsh marigold (Caltha palustris), turtlehead (Chelone species), Joe pye weed (Eupatorium species), sneezeweed (Helenium autumnale), Canadian burnet, (Sanguisorba canadensis), rose mallow (Hibiscus moscheutos), northern blue flag iris (Iris versicolor), cardinal flower and great blue lobelia (Lobelia cardinalis, L. siphilitica), golden ragwort (Senecio aureus), tall meadowrue (Thalictrum pubescens), and Culver's root (Veronicastrum virginicum).
Most of these plants will tolerate light shade. In addition, there are others that actually prefer some shade. Among these are Japanese primrose, Rodgersia species, Ligularia species, and Astilbe species. The native ferns in the Osmunda genus (royal fern, cinnamon fern, and interrupted fern) love moisture. Many sedges (Carex) prefer a shady damp spot, and like ferns they are deer-resistant.
Another alternative to consider for a shady wet spot is a moss garden. Native mosses can be encouraged to spread where grass will die out. They can also be propagated from your local mosses or purchased from a specialty moss nursery; Google Moss Acres to access their website. Moss will not stand up to heavy foot traffic, however.
Sometimes the simplest choice for shade under trees where grass won't grow is just 2 to 3 inches of woodchip mulch (not touching the bark, however). This protects the tree trunk from lawnmower or weedwhip damage. It also helps to improve the soil, conserve moisture, reduce compaction, and keep down weeds. Plus it's a nice place for table and chairs, or the children's sandbox.
So you see there is no shortage of possibilities. As always, a pH test for acidity/alkalinity would be a good idea. A pH test costs $2 at the Tompkins County Cornell Cooperative Extension office.
Ask a Gardener appears weekly in The Journal during the growing season. For answers to other garden, lawn, landscape and pest questions, call Cooperative Extension at (607) 272-2292 or email: email@example.com. This article was written by Patricia Curran, horticulture program manager at Cornell Cooperative Extension of Tompkins County.