I could have titled this post “I pushed the zone and the zone pushed back.” Last spring, filled with thoughts of permanently warm and wimpy winters, I planted a butterfly bush (Buddleia ‘Nanho Purple’). It was supposed to grow up to 6 feet tall and be covered with long clusters of purple blooms from August through September. (This image is from the Missouri Botanical Garden.) The bush seemed to do well, growing to about 3 feet in height with several nice blooms last fall. Butterfly bush is generally a Zone 5 and south plant and grows very large in some climates. Alas, Minnesota is still Zone 4, as this past winter proved. I’ve been watching the bush’s corpse in hopes of seeing some signs of life. None so far; none expected.
This incident drives home advice I heard from a horticulturist about planting for climate change. “Push the zone, if you want,” she said, “but don’t plant anything you can’t afford to lose.”
It also reminds me how grateful northern gardeners should be for the research that has been conducted over the years at places like the University of Minnesota and North Dakota State University. Research has expanded the growing options for gardeners in the north with everything from new magnolias to a wide range of shrubs to better apples. Plant breeding is a long, arduous and often frustrating process. Last summer, I had a chance to visit Harold Pellett (left), a retired U of M researcher and director of the Landscape Plant Development Center in Mound. Pellett, who during his 30-year career at the U helped develop 25 new varieties of shrubs including the Lights series of azaleas, founded the center to continue his work creating plants for the North. The center has already introduced a new ninebark, Center Glow™ ninebark, and a new non-climbing clematis, Center Star™ clematis. Pellett and his fellow researchers, who are based in Oregon, Russia, and lots of places in between, are working on several new varieties of woody plants, including a hardier butterfly bush.
“Will it be hardy enough to be reliable in Minnesota?” I asked him last summer. Pellett gave me one of those gentle, knowing looks that seemed to say, dream on, sister. “More like Iowa,” he said.