Go beyond the beautiful and multiply the purpose
Basil, oregano and dill—recently harvested from the garden—hang from the kitchen cabinets, giving off delightful aromas as they dry. Soon, pieces of them will join flowers as part of a decorative arrangement on the table. When dried, the dill also will give the chicken salad an unexpected twist. The basil and oregano will provide tomato sauce depth and flavor.
Welcome to the world of multipurpose garden plants—plants that provide value in more than one way.
Most people know about a few multipurpose superstars such as aloe vera, a succulent evergreen with leaves that are full of a slimy tissue that contains vitamins, minerals, amino acids and antioxidants. This tissue, often called gel, can be used as a balm on an array of skin issues, including rashes, sunburn and cuts. It also makes an interesting house plant with its spiky leaves. It has other reported medicinal uses as well, but many are unproven.
But how many other plants are there with multiple uses? What benefits do they provide?
Horticulture experts Jamie Dockery, Amy Aldenderfer and Rick Durham, all with the University of Kentucky Cooperative Extension Service, had the same answer: All plants are multipurpose. There are few garden plants that do not have more than one purpose—from wildlife habitat and pollinator food to natural pesticide and kitchen spice—but some serve more purposes than others.
Master Gardener Tracey Easton agrees with the UK horticulture experts. Her expansive yard in Elizabethtown is a living example of multipurpose plants, multipurpose containers to grow them in and unusual habitats for wildlife, including a butterfly house (similar to a birdhouse) designed to shelter butterflies. A hard rain, for example, can kill them or tatter their wings. “The butterfly house provides a little luxury for them,” Easton says.
A walk around Easton’s yard—with sun-loving plants, shade dwellers, herbs, vegetables, wildflowers and those that tolerate wet conditions, among others—is a testament to the beauty and utility that come from variety.
A large maple tree worthy of a painting makes its home in the middle of the yard. In addition to its majestic beauty, the big old tree shades the house, helping lower utility bills, and provides habitat for animals and insects.
“Certain maples are host to the cecropia silk moth,” Easton says. “Trees are the host plant to butterflies and moths.”
While trees are the obvious shelters for birds, some species also nest in potted ferns, wreaths and flowerpots.
You never know what plant might provide a home for insects or animals, Easton adds.
“This summer I stuck my hand in the soil of a potted peace lily to see if it needed watering and grabbed a frog. I never thought to go there looking for a frog, but it worked well for the frog,” she says.
While home gardeners expend energy keeping the wilder critters—like deer—at bay, they can also help out other kinds of life that visit. Those trees of Easton’s, for example: butterflies feast on the tree sap, pollen and rotting fruit, she points out. They also lay their eggs on host plants, which are then chomped on by the hatching larvae. “Each species of caterpillar will eat only a few plants. It’s good to know the host plant for the specific butterfly you would like to see,” she says.
Milkweed is a favorite of the endangered monarch butterfly. Since 1990, around a billion monarch butterflies have vanished, the U.S Fish and Wildlife Service found in a 2015 report.
There is a long list of plants that attract and nourish pollinators like bees and fun-to-watch hummingbirds. Bee balm, cardinal flower, salvias and trumpet honeysuckle are among the best for hummers, according to the National Audubon Society.
Home gardeners shouldn’t cut down those aster, coneflower and black-eyed susan plants after they bloom—they provide seed for birds in the fall and winter as well as beautiful blooms for pollinators in the summer.
When it comes to plants with the dual purpose of repelling mosquitoes and other pesky bugs, the actual results are mixed. Informal lists usually include catnip, lemon balm (caution: it is invasive), bee balm, floss flower, marigold and citronella.
For example, many gardeners border their veggie beds with marigold, which contains pyrethrum—used in insecticides—in the belief that their strong scent repels pests. “There are a lot of people who swear by it and there’s a lot of anecdotal evidence for marigold,” says Rick Durham, extension professor of horticulture at UK. But he adds that research doesn’t show much difference between beds bordered with marigold and those without.
Similarly, the oils and extracts from citronella plants are an ingredient in some of the repellents on store shelves.
“The problem with a lot of these things is that when they’re used outdoors, you’re kind of at the mercy of prevailing breezes,” Durham says.
The best practice remains to have a variety of plants in the landscape to attract beneficial pollinators and insects, he says—but don’t count on one individual type of plant to repel bugs.
A role for weeds
Some plants, such as Dutch clover, have been dubbed bad boys in the war on weeds. Many people use pesticides to eliminate them to ensure their yard looks like a green carpet.
But weeds also have multiple purposes.
“Dutch clover, a herbaceous perennial plant in the bean family, provides an early nectar source for bees,” says Jamie Dockery, who works out of the Fayette County Cooperative Extension Office. Clovers are known for adding nitrogen to the soil, reducing the need to apply fertilizer.
Dandelions are another plant on the “not wanted” list, but Dockery says they are one of the best nectar sources for bees. “Bees living through the winter can be in dire straits come spring, and dandelions are one of first things bees can get to for food,” he says. “There is so much intolerance of dandelions, which is unfortunate. Monocultures of one plant can promote the spread of insects and disease.”
Think outside the bed
In addition to multiuse plants, gardeners can take a wider view toward making their landscaping itself multipurpose. Think tomato plants in the front yard or landscaping with a blueberry bush instead of a burning bush. Examples like these add color, pattern and interest to landscaping in addition to food, according to Amy Aldenderfer, who is based in Hardin County’s Extension Office.
“This isn’t a new idea by any means,” she says. “It’s been done since the beginning of agriculture.
“We tend to create categories and put plants in certain boxes—vegetables, herbs, etc. Those are self-imposed rules you don’t have to choose to follow.
“For example, apple trees are often relegated to the backyard, but they can be a front yard tree as well. They bloom in the spring, and in the fall, you get apples to eat. Pawpaw trees are also pretty and provide fruit.”
Homeowners looking for an alternative to fencing to provide privacy can put larger shrubs and trees, including evergreens, to that use. The trick is to layer the border plants and mix them up. Using multiple species keeps the whole border from being wiped out if disease strikes one particular variety.
Aldenderfer suggests more multipurpose mixes: Instead of a vegetable-only garden, plant a vegetable/herb/flower garden.
“There is the ‘three sisters’ method, (companion planting) corn, beans and pumpkins (squash),” she says. “The pole beans grow up the corn stalks. Planting pumpkins underneath the corn stalk helps keep raccoons out of the corn.”
In Easton’s garden, the stump of an old tree that died has been repurposed. Prickly pear cacti now cover the stump, adding color and texture as well as room for a new species.
The reward for trying new approaches in the garden is year-round, but for Easton spring is extra special:
“When I go outside every spring, I see the flowers and the herbs and the pollinators and think, ‘Oh, I remember that. Isn’t it beautiful?’”
Certifiable wildlife supporter
Home gardeners can have their landscaping designated a Certified Wildlife Habitat by the National Wildlife Federation, which provides an easy-to-follow checklist. The designation covers food, water, cover, places to raise young and sustainable practices.