For gardeners, a trip to the local garden center in the spring is as tempting as a visit to the candy store. How do you choose between your old favorites and all the gorgeous new varieties? And aren’t there lots more new plants every year than you found twenty years ago?
Photo courtesy of Ball Horticultural
Yes, there are indeed many more choices today than in the past. This explosion is due to both the impact of technology and the globalization of the gardening industry.
Developing, growing and marketing new varieties for gardens is big business. According to Bruce Butterfield of the National Gardening Association, about one in three American households (36 million) participate in flower gardening. These households spend $2.3 billion on flowers and their care. In addition, parks, municipalities and businesses now maintain floral displays. This country is in a veritable blooming boom.
And of course the suppliers of plants are anxious to be the ones to market the next big thing. According to St. Louisan Bill Ruppert of National Nursery Products, you may be tempted next year by a black petunia. And here in the Midwest, garden centers will be featuring the annual Angelonia, a snapdragon-like flower that loves heat.
Portrait of a garden enthusiast
For Bill Ruppert, gardening is a both a vocation and an avocation; in short, it is a passion. Professionally, he is a representative for companies that sell plants wholesale to nurseries and landscapers. He is also part owner of a greenhouse in Illinois that raises many of the annual plants in a unique, environmentally friendly greenhouse.
But it is his volunteer gardening activities list that goes on and on. He is happy to report, as a board member of Gateway Greening, that they now have 150 urban gardens in the City of St. Louis. For Gateway Greening, he has designed the planting in Kiener Plaza, Market Street and Tucker Blvd. A Kirkwood resident, he designed the containers in front of its City Hall. He helps choose the Plants of Merit tagged at the Missouri Botanical Garden. He works with Grow Native and ShowMe Rain Gardens, and is on the MoBot Horticultural Advisory committee.
His biggest project at present is the America in Bloom symposium to be held in St. Louis this fall. You can bet those downtown plantings will be spectacular for the event. And at that time, Webster Groves will find if it has won the national community involvement competition, and University City will be gathering pointers for its entry next year. His home Kirkwood won first prize in the community involvement category in 2007.
About that greenhouse. He and his partners have built near a massive landfill owned by Waste Management. Waste Management sells the methane generated in the landfill to Ameren, who turns it into electricity. His greenhouse uses the hot water from the turbines to heat their floors—lowering their heating costs more than 90%. Now that’s green.
In the 1990’s, the original purple wave petunia was the next big thing. This All-America selection comes from Japan. Two Japanese brewing companies were involved in its development. A Suntory scientist discovered a sprawling petunia in its native Brazil. Although Suntory is primarily known as a maker of Scotch whiskey and other beverages, is has a garden plant division as part of its philosophy of “supplying products to enrich our customers’ daily lives.” Seeds from the original plant were sent to a professor in Tokyo, and eventually one of his students took the seeds to Suntory’s rival Kirin. Kirin also has a floral division, and its breeders developed the parents that are crossed to make the hybrid seeds you can buy in packets today. Today the American company Ball Horticultural produces and markets the original wave petunia and its many descendents with Kirin as a breeding partner.
Photo courtesy of Ball Horticultural
The Wave Purple petunia was revolutionary. In additional to unique color, it grew like no other petunia on the market. It could cascade for hanging baskets or it could spread like a ground cover. Wherever a stem touched soil it would send down roots.
The rooting propensity was a boon to independent garden centers because the original wave petunia didn’t do well when grown in the inexpensive six-packs that were the mainstay of the big-box stores. By the time a six-pack of wave petunias was ready to come out of the greenhouse and into the consumers’ gardens, the roots were too entangled to separate. So wave petunias were best grown in four-inch pots that the smaller independent operations preferred. Today, some of the descendants of the original wave petunia even grow well in six-packs.
The wave petunia was developed the old-fashioned way, by breeding for seeds. This multi-year process means that each parent line is inbred for at least ten generations, so that all its progeny are genetically homogeneous. One parent may be bred for color, the other for spreading habit. During the inbreeding process, any progeny plants that differ from the parents are discarded. Finally, a male parent line is crossed with the female parent line. At the time of flowering, all the pollen-producing anthers are cut off of the female, and she is fertilized with pollen from the male. The resulting seeds, called F1 hybrids, will grow into essentially identical plants.
Don’t try to save seeds from your F1 hybrid plants though. They will follow the laws of genetics and produce progeny with lots of variation. Think of it as somewhat like eye color in people. Two brown-eyed parents can have a child with blue eyes if each parent has a recessive blue-eyed gene.
The wave petunia story is representative of how many things were done in plant breeding until about 25 years ago. The explosion of new plants available to gardeners today, though, is due to a layer of technology that preserves newness without extensive inbreeding. This technology is cloning. Plants can be cloned through division, through cuttings, through grafting, and in most new offerings, through tissue culture.
As an example of today’s new plant variety development, take Brunnera macrophylla, a green-leafed perennial that blooms with forget-me-not-like flowers in the spring. The Missouri Botanical Gardens has proclaimed it a Plant of Merit. It is propagated by division. Growers subdivide the plant into smaller pieces.
At some point, a Brunnera macrophylla had a mutation that caused it to have some attractive silvery spots on its leaves. This plant, called Brunnera macrophylla ‘Langtrees’ was divided and divided. When Walters Gardens crossed Langtrees with the parent plant, seeds were produced and planted. Because division had preserved all the genetic diversity in the parents, one or more of the seedlings had leaves with that were more silver than green. The ‘Jack Frost’ seedling was grown and observed for hardiness and other qualities. When it continued to show good traits, it was cloned in tissue culture. In tissue culture, many identical plantlets are produced in a controlled environment and tested to be free of common plant viruses. The Walters Gardens catalog shows that all ‘Jack Frosts’ come from tissue culture.
macrophylla ʻJack Frost.
Photos courtesy of Walters Gardens Inc.
One big trend in home and display gardening is using native American plants. The story of Heuchera (coral bells or alumroot) shows how a Plain Jane but hardy native perennial has been bred into many Fancy Nancy showoffs—again through breeding combined with tissue culture.
Below, Heuchera ʻAmber Wavesʼ
Photo courtesy of Terra Nova Nurseries
Twenty years ago, a few varieties of Heuchera were available; they had plain green sycamore-like leaves with inconspicuous sprays of coral flowers. Heuchera grew well in partial shade, and didn’t demand a lot of water. But a purple-leaved Heuchera from England captivated Dan Heims, president of Terra Nova nurseries in Oregon, and he began to breed the plant for showy leaves. He has developed at least 40 new varieties of this species with leaves of every color, from lime green through peach to “Chocolate Ruffles”, another Plant of Merit. These hybrids break up the ‘tyranny of green’ in perennial gardens when blooms may be scarce.
One parent of Chocolate Ruffles was a plant that one of Heims friends in Oregon had collected in the wild. Indeed, every single ruffled Heuchera hybrid has had this single plant—propagated by tissue culture from the beginning—as a parent. Every yellow-leaved Heuchera has some “Amber Waves” in it. Every successful cross is grown for two years in the Terra Nova nursery, then tissue cultured. The clones are sent for “trialling” all over the country to find where and how they grow.
The trial sites, explains Dr. Allan Armitage, of the University of Georgia, look at new plant strains that are candidates to be introduced commercially. The trial garden at the Kemper Center, at the Missouri Botanical Garden, tests plants that are already on the market.
Most of the plant propagation, either by tissue culture or by cuttings, takes place overseas because these processes are quite labor intensive. Heims of Terra Nova works with labs in Indonesia, New Zealand, Holland, Poland, South America, and soon Moscow. Armitage explains that for the many annuals and perennials that are propagated through cuttings, the foreign growers make many stock plants that can be used to take one-inch cuttings. Hundreds to thousands of these cuttings are sent back to rooting stations in this country, and eventually get to your local garden center.
Little Annie—a St. Louis exclusive
Not all new flowers are developed by professional breeders. Eric Stahlheber, owner of Southernwood Gardens in Jonesboro IL, decided to just take a flyer at developing a coneflower of a different color.He ended up with a coneflower (Echinacea) colored the usual pink. But Little Annie is dwarf (about 12 inches in contrast to the usual 40) and is covered with about three times the usual number of blossoms.
Photo courtesy of Sugar
Creek Nursery
To get Little Annie, he crossed a short-ish variety “Little Kim” with plants having orange, yellow, red or other colors. Of the thousands of seeds, about 400 germinated, and he planted the 50 healthiest looking. One was stunted with tiny leaves, but seemed healthy. He nurtured it, divided it, and interested the wholesale grower Walters in it.
It took Walters two years to establish a successful tissue culture, but Little Annie is now on the market. Sugar Creek Nursery in Kirkwood is the exclusive retail outlet for most of the first 1200 plants. By next spring, Walters hopes to have 50,000 Little Annie’s on the national market. And Eric Stahlheber will reap a royalty from each plant sold.
It wasn’t so long ago that parks were mostly trees and grass, that most home landscaping was lawn and evergreen trees, and that cityscapes were devoid of colorful planters and median strips. Today, from early spring to fall, our eyes can feast upon growing (and glowing) color. And, if we look closely at the planters and gardens, much of what we enjoy may have made been born of American parentage in a far-away land and returned home for our enjoyment.
This article was originally published in the St. Louis Beacon.