Abundant rainfall often leaves low-lying landscapes waterlogged and soggy, creating conundrums for gardeners in the Lowcountry. These poorly drained areas are typically too wet for turfgrass and constructed drainage solutions can be costly. Fortunately, many plants are tolerant or even require consistently wet soil to thrive.
Some plants have developed adaptations that allow them to survive in wet soils. They continue to photosynthesize even with little to no ability to exchange oxygen and other gases through their roots for some period of time. Gardeners can take advantage of these survival strategies and create beautiful gardens with plants that tolerate “wet feet.”
Begin by assessing how wet your problem area is and how much sunlight the area receives.
Take time to research plant needs to avoid time-consuming and costly mistakes. It’s important to note that while many of the plants listed will do well in functional landscape features known as rain gardens, poorly draining, wet areas in the landscape are not the ideal location for rain gardens. The primary function of rain gardens is to move water down into soil, protecting downstream water quality.
I have long admired the deciduous shrub Buttonbush (Cephalanthus occidentalis) but it was not until I moved to the Lowcountry that I had the perfect place to plant one. I created an ornamental garden area in my shady, low-lying front yard with a multi-trunked deciduous buttonbush as the focal point.
When the distinctive pincushion-like white flowers emerge, the bees and butterflies flock to them. For those who garden on the marsh, ducks and other shorebirds enjoy the seeds of this lovely native shrub.
Beautiful Chionanthus virginicus is a widespread native tree that has as many common names as there are reasons to grow it.
Fringe tree, Old man’s beard, and my favorite, Grancy Gray Beard, are among the tree’s nicknames. Reasons to plant it include the ability to thrive in wet soil. Fortunately even gardeners with moderately moist soils can enjoy this near perfect small tree that tops out at a maximum height of 20 feet.
One of the best reasons to plant this tree are the clouds of fringe-like fragrant white flowers that cover it this time of year.
With virtually no disease or pest issues, Grancy Gray Beard is also tolerant of air pollution, making it a good choice for urban gardens. The only reason not to grow this spectacular tree is if you have very dry soil, as it does not tolerate drought.
Louisiana irises are a group of five species of iris native to the Gulf Coast region. The species and their many hybrids are beautiful and reliable. These regal irises brighten shady wet areas with sword-like foliage and flower in spring to early summer. Likewise, Siberian Iris (Iris sibirica) also tolerates a wide range of soil conditions from wet to dry and part to full shade with few pest problems.
As its common name implies, Swamp Milkweed (Asclepias incarnate) or pink milkweed, actually thrives in wet mucky clay soils. Underused in the home garden, this perennial native supports Monarch butterflies and hummingbirds. The pretty, soft pink, fragrant flowers also provide nectar to honeybees. Like other milkweed species, swamp milkweed is easy to grow from seed.
Cardinal flowers (Lobelia cardinalis L.) are a favorite nectar source for hummingbirds from mid-summer through early fall. This native wildflower has showy red flowers that appear along spikes a few feet above the foliage. Perfectly suited for full sun to part shade, this plant is equally at home in consistently moist to very wet soil. Try it at a pond or woodland edge for a bright contrast to dark woods and water.
Bottom line, don’t let wet soggy soil stand between you and a beautiful garden. Take time to research plants for your landscape using online tools such as the Clemson Extension Carolina Yards Plant Database http://bit.ly/1JdcQTB or the Native Plant Information Network’s native plant database found at www.wildflower.org. The South Carolina Native Plant Society has a comprehensive Native Plant List for Coastal South Carolina found at www.scnps.org.
Read more on “Plants for Damp or Wet Areas” in factsheet # 1718 at the Clemson Extension Home and Garden Information Center found at http://bit.ly/1DC5rFL.
Summer gardening is all about water. Too much or too little water is on every gardener’s mind in the Lowcountry.
In the Summer Edition of the Carolina Yards Gardening School, we are focusing on water resources and finding plants for every landscape situation.
Attendees will learn to harvest rainwater for future use, turn wet areas into bogs using carnivorous plants, create floating wetlands and find the perfect perennial for the wettest or driest spot in the yard.
Cost is $55 before May 21 and includes a soil sample and “Rain Gardens: A Rain Gardening Manual for South Carolina.”
The Ashley Cooper Stormwater Education Consortium is holding its third annual rain barrel sale in May. The Ivy rain barrel is a 50-gallon rain barrel that is USA-made out of recycled plastic and comes with everything needed to start collecting rainwater from your rooftop. This is a three-day event with pickup locations in Summerville on May 28, Goose Creek on May 29 and Charleston on May 30. Preorders required. Learn more and to place an order visit rainbarrelprogram.org/ashleycooper.
Amy L. Dabbs is a Clemson Extension Urban Horticulture Extension Agent. Send questions to firstname.lastname@example.org.