By Erin O’Farrell
One of the most important (and exciting!) parts of designing and building your rain garden is choosing your plants. The best plants to grow in your rain garden depend on the location of your garden and how much sun your plants will get. Not all plants love full sunlight so it’s important to know what they prefer before adding them to your garden. The plant lists in this post will help you pick the best plants for your rain garden.
The majority of the plants we use to fill our rain gardens are native so they have a high likelihood of survival and tolerance to the conditions of this area. They also are plants that support local pollinators which is one of the most rewarding things to see in your established rain garden.
What is a rain garden?
A rain garden acts as a personal water quality system, capturing and filtering runoff from your roof and lawn and recharging the groundwater. Many people choose to direct a downspout from their house into a rain garden to help capture and sink water from their roof.
Middle Tennessee is receiving more frequent and heavier rain events. These heavy rain events often bring flash-flood conditions that are destructive to our land and water, and in extreme cases, our lives.
Stormwater from these rain events flows faster, dirtier, and with more force into our rivers and streams, causing pollution and erosion issues. On scales large and small, it’s important that we create space to capture and sink (infiltrate) stormwater where it lands to reduce the amount of water overwhelming waterways during rain events.
A properly constructed rain garden can capture and filter more than 40,000 gallons of stormwater each year!
While a rain garden won’t prevent extreme flooding, it’s one tool in the toolbox we can use to mitigate the effects of flooding, increase community resiliency and prevent surface water pollution, especially in urban areas.
What do I plant in my rain garden?
Now you know the basics of what a rain garden is and why it is such a helpful tool. Great! But how do you build one? And what plants should you plant in your rain garden?
To find instructions on how to build a rain garden, check out this useful manual we’ve put together. It will tell you more about rain gardens, how to design and build them, and how to take care of them.
The Cumberland River Compact has worked with our community here in Nashville to plant more than 500 rain gardens since 2009.
All of this experience means we know a thing or two about which plants grow successfully in rain gardens in our area. We like to use perennial, native plants in our rain gardens to help minimize care and maximize growing success. Many of the plants in these lists are also pollinator favorites! We’ve highlighted three perennial sun plants, three perennial shade plants, and three trees/shrubs that we use the most in our rain gardens to help you choose which plants to plant in yours. We’ve also included plant lists from our Rain Garden Manual to give you a variety of options to choose from!
PLANTING TIP: Always arrange your plants in your rain garden BEFORE you plant them to see if everything fits and you like the layout, and to make sure tall things won’t out-compete shorter plants.
Plants for a Full-Sun Rain Garden:
If you’re planting a rain garden that gets a lot of sunlight, our go-to plants are coneflowers, black-eyed susans, and beebalm. Besides helping collect and filter stormwater, they add beautiful color and attract all sorts of pollinators to your garden! Read more about them below:
Echinacea purpurea
(Purple Coneflower)
Coneflowers are hearty native flowers that draw all types of pollinators to your garden with their bright color and seeds. Blooming in midsummer through fall, these tough flowers grow quickly to 2-4 ft in height and are an excellent, low-maintenance plant for new gardeners. The plant is a self-sower and flourishes during the heat of Tennessee summers.
While coneflowers do best in rich soil, they are very tolerant of poor soil conditions. Coneflowers can be started from seed indoors in the spring, or planted as small plants in early summer. Plant the flowers 1-3 feet apart, watch them flourish, then cut back the flowers in the fall when tidying up your garden for the winter.
Rudbeckia hirta
(Black-Eyed Susan)
Black-Eyed Susans, native to North America, are one of the most popular wildflowers grown and a great option for your rain garden. The plants bloom from June to October and draw a variety of insects who are attracted to the plant’s nectar and bright yellow flowers. Black-Eyed Susans can grow to over 3 feet tall and tend to spread quickly wherever they are planted- make sure they don’t squash other nearby flowers in your garden!
While they prefer fertile, well-drained soil, the plant can tolerate tough conditions, making them hearty and low-maintenance for your garden. Cut them back after their first bloom to experience a second (sometimes smaller) bloom of the flower in the fall.
Monarda didyma
(Beebalm)
Beebalm, also known as wild bergamot, is a great addition to any rain garden for its fragrant foliage and bright colors. As a member of the mint family, the plant has a long history of medicinal use and can be used in herbal teas, salves, salads, and as a garnish to your meal. Growing up to 4 feet in height, beebalm stands tall as a vibrant plant, drawing hummingbirds, butterflies, and bees to its flowers and birds to its seed heads during the fall and winter months.
Plant beebalm in the spring or fall 18-24 inches apart in well-draining soil. Make sure the plant has good air circulation in your garden to prevent it from developing mildew on its leaves. After the plant blooms once or twice in the summer – showing off its bright red flowers and fragrant aroma – cut its stems back to 2 inches above the soil after the first frost in fall.
Plants for a Full-Shade Rain Garden:
If your garden gets more shade than sun, we recommend planting hostas, ferns, and alumroot plants. All of these plants thrive in shady conditions and are hardy and easy to care for once established- they are perfect, low-maintenance plants that will be around for a long time! Here’s more about them:
Hosta
Hostas are hardy, reliable perennials that are easy to grow and will serve as a long-lasting addition to your rain garden. The plant comes in a variety of colors, patterns, sizes, and heights, making it easy to find one that works best for your garden space! Buy hostas as potted plants and plant them in the spring or fall in moist soil. While they are mostly known for their foliage, hostas produce pretty flowers in the summer and early fall months.
Once established, the plant can withstand heat and mild droughts, but are a perfect plant for your rain garden, as they prefer wet soil. After the first few touches of frost at the end of fall, cut your hosta back and remove brown leaves for the winter months. Hostas are popular plants for deer and other wildlife to munch on, so be aware of any wildlife that may take a liking to your garden when thinking about planting.
Polystichum acrostichoides
(Christmas Fern)
Christmas ferns are a great perennial that requires minimal effort to grow once established in your rain garden. This evergreen plant will also stay colorful during colder months when your other plants lie dormant, adding a pop of brightness to your garden during wintertime!
Plant Christmas ferns in moist soil after the last frost of the spring. While the plant can survive in mildly dry conditions, make sure your ferns get a lot of water during the heat of the summer. The fern’s fronds will grow up to 4 feet tall and create beautiful foliage for your garden year-round.
Heuchera americana
(Alumroot)
Also known as Alumroot, Heuchera is one of the easiest perennial plants to grow. The plant is tolerant of a wide range of heat, weather, and soil conditions. Alumroot comes in a wide range of varieties, allowing you to choose from different combinations of foliage and flower hues to pick a plant that best suits your garden!
After planting in the fall or spring in moist soil, the Alumroot plant is virtually carefree. Just make sure it’s getting enough water during dry spells and trim back its foliage in the spring to enable the best growth.
PLANTING TIP: Use your largest plants like trees and shrubs to be the anchor points in your garden, laying them out first and filling in with other smaller plants.
Trees & Shrubs for your Rain Garden:
Looking to add some larger plants to your rain garden? Need some more shade for the hostas you just planted? Trees are great at providing shade and sturdy root systems and are great investments for your rain garden. Plus, their leaves provide beautiful foliage year-round, especially during their blooming season in the spring! We like to plant redbud, flowering dogwood, and oak-leaf hydrangea trees in our rain gardens. Learn more about them here:
Cercus canadensis
(Redbud)
Redbud trees are a great addition to add shade and color to your rain garden without taking up a lot of space. Redbuds grow to about 20-30 feet in height and can span up to 35 feet in width, providing shade to plants in your garden that prefer full or partial shade conditions.
The tree’s beauty shines through in early spring, when its bright pink blossoms burst for 2-3 weeks and create a pop of color to spring scenery. Plant your redbud tree in spring in well-drained soil in partial shade. Redbuds require minimal maintenance once established; trim off dead branches as needed and make sure enough moisture gets to its trunk.
Cornus florida
(Flowering Dogwood)
Flowering dogwood trees provide beautiful scenery, a good root system, and shade for your rain garden. This deciduous tree is small in size, growing to about 30 ft tall at most, and is well known for its year-round beauty.
In the spring, the tree produces stunning bright white blossoms during its 2-3 week blooming season. In the summer, the rich green foliage adds to verdant scenery, and in the fall, reddish-purple leaves grace its branches. During the winter, the tree produces pretty, but inedible, red berries loved by many bird species. The trees do best in partial shade or near other, larger trees.
Hydrangea quercifolia
(Oak-leaf Hydrangea)
Oak-leaf hydrangeas – named such for their oak-shaped leaves- are a deciduous shrub that can grow up to 8 feet tall. Its leaves turn red and purple in late fall before becoming a verdant green in the summer months. The shrub also produces clusters of white blooms in the springtime, which gradually turn purple in the summer and make for pretty flowers.
Oak-leaf hydrangeas are easily grown in moist soil and do best in full sun to partial shade. The plant is a great option for those looking to plant a bigger shrub/small tree in their rain garden but don’t want to invest in a taller, more costly tree.
Grasses & Sedges for your Rain Garden:
Grasses and sedges are a great way to fill space and add color and dimension to the garden. They’re also hardy and tolerant to a range of conditions! The three types of grass and sedges we use most commonly in our rain gardens are Switchgrass, Little Bluestem, and Hard Rush.
Check out our rain garden manual and blog post on how to design a rain garden for more resources and info for making a rain garden in your backyard!
Where to buy rain garden plants
Many nurseries are beginning to incorporate native plants into their stock, others specialize in just native plants! Here are a few we love:
5850 John Bragg Hwy, Murfreesboro, TN 37127, US
335 Nichols Ln, Gallatin, TN 37066
BATES NURSERY AND GARDEN CENTER
3810 Whites Creek Pike, Nashville, TN 37207
7190 Hill Hughes Rd, Fairview, TN 37062
Erin O’Farrell is the Communications Coordinator at the Cumberland River Compact, where she leads storytelling efforts across the organization’s programs and supports marketing and communications initiatives. Erin has a degree in Environmental Studies from Bates College. Originally from Vermont, Erin lives in Nashville with her partner, Zoe, and their pets, Emmylou and Pepper. She enjoys spending time outdoors, reading, and exploring the beautiful Cumberland River basin.