December 6, 2016

Visiting Trial Gardens Can Help You Choose Plants

Tired of using the same old plants in your garden and containers every year? Tired of buying plants that look great at the garden center but perform poorly at home? Well, think about taking a ride to a trial or display garden in your area.

Several steps take place when a new plant variety is developed, and before it’s available for purchase. Once a plant breeder has a stable new variety, they sell it to a plant propagator who grows large quantities of it. These small plants are in turn sold to a grower who transplants them into cell packs or individual pots and grows them. Then the grower sells them to plant wholesalers, retailers and mail-order houses where you are able to buy the plant.

Along the way, a plant breeder or propagator wants to make sure that their new variety is fit for your garden. This is where trial gardens enter the picture.

Michigan State University (MSU) has extensive trial gardens for annuals, vegetables, native plants and herbaceous perennials. Being located in USDA Zone 5 puts their gardens in the same growing zone as most of the state, which is good news for home gardeners. Over 500 different cultivars are submitted by breeders, seed companies and nurseries to be tested in the MSU gardens. “We test plants that are suitable to grow in Michigan and evaluate these plants using a five-point system,” says Katie McCarver, MSU trial garden manager. “One means the plant died, and five means the plant is awesome in terms of producing nice blooms, pest resistance, and being true to habit.”

Evaluation starts two weeks after the plants are put in, around May 15-20. Then, they are evaluated every two weeks until the last frost. Each evaluation takes a whole day for McCarver and Art Cameron, MSU garden director, to assess all the varieties. Plant performance is dependent on a number of factors, including soil and weather conditions.

“Companies are looking for honest evaluations,” McCarver explains. “I have to determine whether it’s a failure in our growing conditions or breeding that causes a plant to die. Some plants just don’t perform well.”

Michigan State is also an All-American Selections (AAS) Trial Garden. “Think of All-American Selections as the Good Housekeeping seal of approval for plant varieties,” comments AAS board member, Jenny Kuhn. AAS has trial gardens throughout the state and the country, and “Tested Nationally and Proven Locally” is their new tagline. Kuhn is also product specialist at C. Raker and Sons, a plant propagator in Litchfield, MI, which also opens its trial gardens to the public.
“Often, big-box stores sell plants that are bred to look well on their shelves to attract buyers,” Kuhn adds. “But these plants do not necessarily do well in your garden. In AAS trial gardens, we are looking for plants that look well at retail but also perform in peoples’ gardens.” The AAS website offers both lists of its winners and trial gardens throughout the state.

In Michigan, plants are starting to look their best by mid-summer, so mid-July through mid-August are the best times to visit these test gardens. While you’re there, Kuhn recommends making notes of variety names that appeal to you, since most local garden centers are happy to order them for you.

For more information on visiting MSU’s gardens, see hrt.msu.edu./our-gardens. There is a good brochure and map you can pick up at the information booth (open June through August) near the garden visitor parking lot.

If you can’t visit the MSU gardens, don’t worry—Katie McCarver posts early favorites on the web in mid-July, and a full report in October. You can also find last year’s top-rated plants at gardens.hrt.msu.edu/ by clicking “Top Performers” in the left sidebar.