What the plant industry is talking about
Rick Darke photo by Ralph Vituccio; Doug Tallamy photo by Jon Baldivieso
I go to gardening or “green industry” conferences and shows—lots of them: Garden writers’ (GWA) conferences, landscapers’ symposia, home and garden shows, flower shows, and, recently New England GROWS. Soon I will attend the Tropical Plant Industry Exhibition (TPIE), an event produced by the Florida Nursery, Growers, and Landscape Association, the nation’s largest association of its kind.
Attending these events serves many purposes: learning, networking, reviewing books and speakers, and checking out products, styles, plants, and trends. As a garden writer and teacher, my job is to report to homeowners and gardeners what the industry is talking about. What plant problems and solutions have been discovered? What are the gardening trends and directions according to national and international horticulture experts? What plants and products are coming your way? I’ll touch on some of the weightier topics at New England GROWS (Boston, Massachusetts) and the 2015 Garden Writers’ Conference (Pasadena, California).
Authors Doug Tallamy and Rick Darke
What Rick said
One of the hottest books of 2015 is The Living Landscape: Designing for Beauty & Biodiversity by Rick Darke and Doug Tallamy (Timber Press). Rightly so. You may remember my frequent references, in talks and articles, to Dr. Tallamy’s important Bringing Nature Home (Timber Press, 2009), a paradigm-changing, eye-opening book about the critical importance of using native plants in home landscapes. The entomologist made crystal clear why we must choose native flora specifically for the survival of ecologically necessary native insects. The book changed or reinforced the way many of us—including regional designers and influencers such as Lyn Chimera, Ken Parker, Dave Majewski, Nancy Smith, Buffalo Riverkeepers’ leaders, and me—teach and implement landscape and garden design. Those named and many others were already practicing and promoting native/ecologically sound gardening, but Doug Tallamy captured the urgency and distilled the lessons as had never been done before.
In the new book, with the masterful photographer, landscape designer, and prolific author Rick Darke, Tallamy expands on what constitutes a truly living landscape.
At New England GROWS, Darke spoke to several hundred landscapers and landscape designers about the topics covered in The Living Landscape. He said that landscapes must be diversely functional—humans are part of the landscape—and diversely biological. To make that happen, we need not only native plants, but also a consciously layered landscape. He reminded us of the equally important below-ground biology. He redefined sustainability to allow for natural transitions in and maturation of landscapes, and provided examples of long-term designs—the opposite of highly managed, “groomed” yards. He provided inspiration and a challenge for growers, plant sellers, and designers to use multi-purpose plants and not just pretty ones.
Watching the hundreds of nursery professionals and landscape company employees in the audience, I wondered what each took home from the talk: Some are probably already working in the diverse/sustainable landscape field. Others perhaps attended reluctantly but came to question their yews-and-euonymous, clip-and-spray routines. I hope so; I know I will continue to communicate the Tallamy-Darke paradigm.
Clockwise from top: garlic mustard, Japanese knotweed, a poison oak-eating goat, herbicide warning sign in the front yard of a nursery school
About the bad guys
It takes only a few years for invasive species, both plant and animal, to undo a functioning ecosystem. When exotic and invasive species enter natural or designed landscapes, they have no natural enemies or controls. They consume or overrun native and desired plant species, thereby wiping out food and housing for native insects, birds, and other animals. The invaders form monocultures that have no wildlife value. Non-native invasive species (NIS) wreak havoc quickly and seem nearly impossible to eradicate.
Dr. Lois Berg Stack of the University of Maine spoke to some 400 industry folks—mostly landscapers I guessed (by hat and jacket logos). She reviewed the difficult basics:
• Target and prioritize/choose your battles
• Assess neighboring lands where you can’t control
• Know the enemy (biology)
• Know your site and the relevant ecology that supports desirable replacements
Then she talked ED and RR—early detection and rapid response methods, species by species. Once a site is targeted for rapid response methods, project managers have the following possible tools:
Mechanical controls: Examples: Hand pull autumn olive, then pull or rake seedlings. Sever barberries below ground, or hand pull in moist soil. Pull/uproot garlic mustard before seeds develop.
Biological controls: Insect predators have been identified for such well-known invasive species as Purple loosestrife (two beetles are greatly diminishing its spread), Mile-a-minute vine (Persicaria perfoliata), and Japanese knotweed, and Phragmites.
Goats: While technically a biological control, goats stand alone (well, actually in little groups rented by the week) in their enthusiasm for eating many invasive plants. They consume Japanese barberry, multiflora rose, Japanese knotweed, buckthorn, honeysuckles, poison ivy, and more. (The Goatscaping Company in Massachussetts is a fine business model.)
Build the database: Dr. Berg Stack asked all who have managed invasive insect or plant infestations to help build the database. Tell your story to email@example.com. See also Nonchemical Management Options for Invasive Plants at extension.umaine.edu.
Speakers in several settings addressed chemical pest controls and herbicides—effectiveness versus health and environmental costs. Lois Berg Stack informed us of the World Health Organization (WHO) report that glyphosate, the primary ingredient in Round-Up, is now suspected to be carcinogenous to humans (EPA studies in progress). Darke also reported that residual Round-Up has been found in anaerobic environments below ground.
Tracking the bad insects: No good plant show happens without the presence of Cooperative Extension, USDA Forest Service, Department of Environmental Conservation, and other agencies that represent ears and eyes on immediate pest threats. Educational booths covered the Emerald Ash Borer and Asian Longhorned Beetle (plus innocent look-alikes) thoroughly, as well as slightly less familiar pest threats such as the red Lily Leaf Beetle, the Brown Marmorated Stink Bug, and the Spotted Lanternfly. I stopped collecting materials because I know we will find the information at our own Plantasia, the Home and Garden Show, and other science-based regional programs.
Plants: new, rediscovered, better, or trending
Talks on new plants, or great plants according to experts, always draw crowds. In Boston, I attended Cornucopia of New/Almost New Flowering Shrubs and Small Trees, by Michael Dirr, and New Annuals and Perennials for the New England Landscape by Mark Dwyer. In Pasadena, I attended Plant Introductions by Dan Heims (Terra Nova Nurseries), Diane Blazek (All-America Selections), and Barry Yinger (Star™ Roses). I was also inspired by Brave New Vegetable World, including the goods on ‘Ketchup ’n’ Fries’ (the tomato grafted onto a potato!). n
Sally Cunningham (CNLP) is an author, columnist, garden speaker, and tour director for Great Garden Travel (AAA). She consults on home gardening and landscapes privately as well as at Lockwood’s Greenhouses in Hamburg.