How Does Your Garden Grow?
Expert Answers to Your Garden Dilemmas
No matter how long you’ve taken care of your garden, there’s always something more to discover and an unexpected problem or two to solve. To get the inside scoop, we asked experts from the area’s leading horticultural institutions to shed light on the questions they hear all the time from home gardeners.
What’s bugging my plant?
Ever wonder what that tiny insect is, what it’s doing to your plant, and what you should do about it? Wonder no more. You can get help diagnosing your pest problems any time of year from the Morton Arboretum in Lisle, the Chicago Botanic Garden in Glencoe, and University of Illinois Extension Master Gardeners in St. Charles.
According to Sharon Yiesla, plant knowledge specialist in the Plant Clinic at the Morton Arboretum, two of the most popular questions about infestations relate to the emerald ash borer and the viburnum leaf beetle. Homeowners are asking if they should continue to pay for treatments to fight the emerald ash borer in their trees. “It’s still here,” says Yiesla. “Some of these injectable products have been very effective. To stop now is a risk.” She suggests that homeowners consider whether it is more cost effective to let a tree decline or to keep treating it every year.
The viburnum leaf beetle is relatively new to Illinois but it is causing a lot of damage. “It can really exfoliate a plant,” says Yiesla. “One year of infestation won’t kill the plant but two to three years could.” She recommends that you check viburnum shrubs in winter and early spring for signs of the beetle eggs, which look like little footballs on the tips of twigs. Then cut off four to six inches of the infested twigs and dispose of them before the beetle reaches full development. The Morton Arboretum website has a full page devoted to the problem, including lists of viburnum species that are either susceptible or resistant to the beetles.
What is this mystery plant?
“What is this thing growing in my yard?” you might ask. The horticulturists at the Chicago Botanic Garden have yet to be stumped by a question about plant identification. “Weeds are very, very popular,” says Dori Flerlage, horticultural specialist, of the questions that the Plant Information Service hears once the growing season starts. “We are a free service for anyone across the country and around the world,” she says. Last year, the Botanic Garden answered more than 35,000 questions from gardeners as far away as Australia and Greece. For the best results, send a digital photo of the entire plant with an idea of the size of the plant. “It’s like detective work. It may take us some time,” Flerlage adds.
The staff and Master Gardener volunteers also answer requests to diagnose a problem with a plant and general questions on good gardening practices and plant selection. If you want to check out a particular plant in the Garden, the Plant Information Service can look up the location of the plant on its database or you can do it yourself with its Garden Guide app.
How do I know if this is a good plant to buy?
When the greenhouses are teeming with new plants, how can you tell whether the plant you pick out is healthy? Liz Omura, Idea Garden curator at Cantigny Park in Wheaton, advises you to turn over the pot and take a look at the root system. “The roots should be nice and bright and white,” she says. If a plant is root-bound, you’ll have to be prepared to cut away some of the roots or pick a different plant. Another telltale sign is lack of new growth in the plant itself. “You’re always going to see dead leaves but you should also see new buds,” she says. If the main part of the plant is sparse and the soil is wet, you may be looking at a plant that has been over-watered. “Most people over-water,” according to Omura. “The plant tends to look the same, with a lot of yellow leaves, whether you over- or under-water it.”
Cantigny hosts its annual Greenhouse Open House on May 6, where you can see the plants being grown for the park’s soon-to-be renovated gardens and ask the staff your questions. While you shouldn’t be afraid to turn over a plant to look at its root system for fear of damaging it, Omura suggests it’s good form to ask permission first. You might also snag a bargain on plants that the staff doesn’t plan to use in the gardens.
Why should I incorporate native plants?
Native plant expert Janie Grillo, who is presenting on the topic at the Chicago Flower and Garden Show on March 18, hears that question a lot. “They offer a lot of beauty, they are good for the environment and your garden, and they are very reliable. They have evolved in our soils and in our climate,” she says. Grillo should know, having worked with native plants for the Natural Garden and now with Midwest Groundcovers in St. Charles. She likes to mix native plants with ornamentals in her own yard, but cautions that you should do your research to avoid native plants that might take over the yard. In her seminar, she will cover 12 of her favorite native plants, which she prefers for their ability to help pollinators, birds and other wildlife find a lovely habitat in suburbia.
The Chicago Flower and Garden Show, which runs from March 14 through 18, is a great resource in itself, with two dozen display gardens to view, daily presentations by gardening experts, designers and chefs, potting and floral arranging classes, activities for children, and a giant home and garden marketplace. Details are available at www.chicagoflower.com
How can I keep my lawn looking its best?
Mow often and mow high with a sharp mower blade,” advises Richard Hentschel, horticulture educator for University of Illinois Extension in St. Charles. He explains that you should never remove more than one-third of the grass blade at any one time. “When the lawn is longer, the grass shades the ground, conserves moisture, and keeps weed seeds from germinating,” he says. “If the grass is four inches tall and you mow to two inches, it takes a few days to recover and weeds are not stunted.” The sharp blade is “purely aesthetics. The lawn will look much better.”
To water or not is another question. Hentschel suggests making that decision up front, as it impacts how often you will need to mow and fertilize. For Kentucky bluegrass, which is a type of grass often used here, the optimal blade height is two and a half to three inches. When the heat of summer turns the grass to brown, let it be. The dormancy is natural and the green will return in the fall.
What if I don’t have a green thumb?
Don’t tell that to Nancy Carroll, a member of the Naperville Garden Club and two other garden clubs. “Everybody can do something,” she says, when it comes to gardening. “Find the plants that will work for you.”
Carroll helped a busy young family across the street plant flowers near their mailbox, choosing blue and black salvia, which thrive in full sun and don’t need a lot of watering. She suggests parents let their children pick out a few annual plants when shopping at a garden center so they will get acquainted with the joys of gardening. “Then you can tell them, ‘Let’s go water your flowers,’” she says. Carroll encourages fledgling gardeners to check out books at the library, attend seminars at garden centers, ask a Master Gardener, join a garden club, or just learn from experience.
Carroll first joined a garden club when her children were small and has learned a lot from her fellow club members, who, she says, are nothing like the stereotype. “It’s made up of a lot of different kinds of people.”
After trying your hand at growing a beautiful container or flowerbed, you might just find yourself joining the club.
Inspiration and Help for Home Gardeners
It’s easy to find answers to your questions directly from the experts. To get a problem diagnosed, you can call, e-mail a photo, or visit the plant specialists in person and bring in a sample of an insect or a cutting of a plant in distress. See each center’s website for a wealth of information, as well as hours of operation and restrictions on bringing in certain diseased plants and pests.
Morton Arboretum Plant Clinic
Phone: 630 719-2424
Visit: 4100 Illinois Route 53, Lisle
University of Illinois Extension Master Gardener Help Desk
Phone: 630 584-6166
Visit: 535 South Randall Rd., St. Charles
Phone: 630 955-1123
Visit: 1100 Warrenville Rd., Suite 170, Naperville
Chicago Botanic Garden Plant Information Service
Phone: 847 835-0972
Visit: 1000 Lake Cook Rd., Glencoe
Special Garden Events
Chicago Flower and Garden Show: Navy Pier, Chicago, March 14 – 18
Cantigny Park: Greenhouse Open House, May 6; Grand Opening of the New Leaf Gardens, mid-July (date to be announced)
Morton Arboretum: Edible Gardening Workshop Series, March 13 and 24, April 7 and 14; Arbor Day Weekend Celebration, April 27 – 29
Chicago Botanic Garden: Orchid Show through March 25; Get Growing Weekend, May 18 – 20
University of Illinois Extension: Four Seasons Gardening Home Winter Webinar Series, March 13, 15, 27, and 29. Register for free live sessions at go.illinois.edu/4seasons_webinars or watch later on YouTube. Check back for webinars on the next three seasons.