Sure, keeping rainwater on our properties is way better than having it wash away into storm sewers and eventually into our Great Lakes (picking up pollutants as it goes). At the same time, who doesn’t want to jump on the Grow Your Own bandwagon? But creating an edible rain garden? That had to be music to the ears of all the hyphenate multi-taskers in the room.
I was at the Landscape Ontario open house to check out their trial gardens and the event included a fascinating presentation by two speakers on what goes into building a rain garden and the kinds of plants you can use. Sean James of Fern Ridge Landscaping & Eco-Consulting covered the how-do-you-make-a-functioning-raingarden-that-actually-looks-pretty part. His inspiring slide show presentation proved that rain gardens can work (filtering the water and then releasing cleaner water back into the environment ) and still look beautiful. And, get this, you can create a rain garden that looks terrific year-round.
So he had most of us at “Rain gardens give you the chance to use plants you might not get a chance to use”. But then he went on to mention that there are some lovely yet uncommon garden plants that not only add beauty to a rain garden but can be a tasty talking point at your next dinner party. Now there’s an idea “as large as life and twice as natural” (to borrow from Lewis Carroll). Below is a small selection of suggestions from Sean. Bonus: All these plants defy the old assumption that native plants are not showy or beautiful. These are all native to Ontario and parts of the U.S. (Click on the Latin name of each plant to take you to more info and a good photo of the plant).
5 WILD PLANTS FOR AN EDIBLE RAIN GARDEN
Agastache foeniculum (Anise Hyssop): A native of most of Canada and the northern United States, this pretty perennial is a member of the mint family and its leaves make an excellent tea. The showy spikes of small purple-blue flowers, blooming from mid-summer into early fall, attract hummingbirds and butterflies. Considered very easy to grow from seed. Plant this wildflower along the berm of your rain garden in areas that have moist to dry conditions.
Aronia melanocarpa (Black Chokeberry): This deciduous shrub, growing from 3 to 6 feet both high and wide, is a native of eastern North America. The 5-petaled white flowers grow in gorgeous clusters and the dark green leaves give a brilliant red show in the fall. It loves boggy soils but tolerates a wide range of conditions though it’s best to plant this handsome shrub in full sun for best fruit production. The glossy black berries are bitter if eaten straight off the bush (hence it’s common name) but they make great jams and jellies.
Caltha palustris (Marsh Marigold): This mounding perennial, growing to 18 inches at most, is a member of the buttercup family with the bright yellow five-petalled spring flowers to prove it. It’s native to all parts of Canada as well as the west coast and north eastern United States. You can plant this in the part of your rain garden that offers wet to moist conditions. The only challenge with this plant is that it loves consistently moist to muddy conditions so if your rain garden dries out in the middle of a drought, you’ll need to do some extra watering. You can harvest the young leaves in spring and cook using two or three changes of boiling water and pickle the closed buds as a substitute for capers but there are precautions for consuming any parts of this plant. Read up on cooking Marsh Marigold before eating!
Lindera benzoin (Spicebush): A native shrub of Ontario (as well as most of the eastern seaboard in the U.S.), Spicebush leaves and twigs smell spicy when rubbed or crushed. You’ll be treated to small fragrant yellow flowers in spring, glossy green leaves through the summer and red berries in autumn. The dried berries make a good substitute for allspice. Bonus: Birds, butterflies and bees love this shrub and Swallowtail butterflies use it as a larval host. Plant this shrub in the deepest part of your rain garden. It loves moist earth and can withstand floods and standing water (for up to 24 hours). Typically growing from 6 to 12 feet high with a wide, rounded habit, you’ll want to use this large shrub for height and structure in your plantings.
Viburnum trilobum (also called Viburnum opulus subs. trilobum or Viburnum opulus var. americana) (Highbush Cranberry): Another native of Ontario, this shrub can grow up to 4 metres/15 feet high. Sean noted that this plant gives you four seasons of interest with beautiful showy white lacecap flowers and maple-like leaves that turn bright red in autumn. Though this cranberry bears little resemblance to the plant that fills grocery store shelves around Thanksgiving, the berries taste much like common cranberries and are rich in Vitamin C. This shrub can be planted in the basin of your rain garden.
A word about where to establish an edible rain garden: Though many people will eye their ditches as the perfect spot for a rain garden, a ditch is not the place to grow edibles. Contaminants from water usually never make it to a plant’s fruit, staying in the stems and leaves instead (so you’re relatively safe to plant a Highbush Cranberry, for instance), but several of the plants listed above are included because the foliage is edible. To be completely safe, site an edible rain garden where it will receive uncontaminated rainwater such as run-off from a hillside, away from roof, driveway and ditch run-off.
For anyone in the Greater Toronto area, you can find out way more about plants for your own rain garden when Sean speaks during the Toronto Botanical Gardens Lecture Series in November. My prediction is that his talk, “What to do with a Downpour – Ornamental Ways to Handle Rain Water” will be very informative and highly entertaining. Bring a pen and lots of paper. You’ll be writing down all kinds of ideas for creating a wildly beautiful rain garden, edible or otherwise.