If plants were actors, wisteria would be Liz Taylor in “Who’s Afraid of Virginia Woolf.” The jaw-dropping beauty of this vine when it’s in full flower is unequalled; it’s also so treacherously vigorous that it will pull down a wimpy arbor and eat it for breakfast. But now wisteria lovers can relax and put away the shears. Rice Creek Gardens, a Minnesota nursery, has created a wisteria that is both beautiful and well-behaved. Wisteria macrostachya ‘Blue Moon’ blooms with fragrant chains of blue-purple flowers three times a year (June to September) and survives harsh winters. It will cover your pergola in no time, and though it still needs pruning and sturdy support, it’s much less likely to come after you with a broken bottle.
Common name: Blue Moon wisteria, Kentucky wisteria
Botanical name: Wisteria macrostachya ‘Blue Moon’
Plant type: Deciduous perennial vine
Zones: 4 to 9
Height: 15 to 25 feet
· Sun: Blooms best in full sun
· Soil: Average, well-drained
· Moisture: Average to moist
· Mulch: Mulch to preserve moisture in the soil.
· Pruning: Prune in fall, after it finishes blooming.
· Fertilizer: None needed.
· By seed, cuttings or division
· Layering—bury a low branch in the ground, where it will develop a set of roots.
Pests and diseases
· Aphids, scales, mealybugs, leafminers
· Virus diseases, crown gall, dieback
· ‘Blue Moon’ is less aggressive than the more common Japanese wisteria (Wisteria floribunda), but still requires stout support. Train it on a sturdy pergola, arbor, or fence.
· If your wisteria grows overhead, be sure to train it high enough to allow room for the dangling, foot-long racemes of blooms.
· In warmer parts of the country, Asian wisterias are considered invasive. Kentucky wisteria, because of its more docile behavior, has a better reputation, but check locally to see if it’s allowed.
· All parts of wisteria are poisonous, especially the seeds.
· Other cultivars of Kentucky wisteria (Wisteria macrostachya) are available: ‘Abbeville Blue’, ‘Bayou Two O’Clock’, and ‘Clara Mack’, a white-flowering vine.
All in the family
· Other members of Fabaceae include the golden chain tree (Laburnum) and the sweet pea (Lathyrus odoratus).
· Other types of wisteria include Chinese wisteria (Wisteria sinensis), American wisteria (Wisteria frutescens), and silky wisteria (Wisteria venusta).
(Text by Elizabeth Noll, photo of ‘Blue Moon’ courtesy of Monrovia)