I have mixed feelings about growing and promoting butterfly bushes. On the one hand, they are beautiful and reliable garden plants; On the other hand, their cynical nature cannot be denied. Keep these facts in mind before purchasing one of these shrubs.
Butterfly Bush Facts
The weedy and invasive nature of butterfly bush is due to seed production. Butterfly bushes are widely adapted to a wide variety of conditions, settling easily into natural and disturbed landscapes—even concrete cracks (pictured below).
During our six-year trial at the Chicago Botanic Garden, plants in our garden were observed at non-weedy levels. Butterfly bushes should not be grown—or grown with caution—in areas where they have become a nuisance. B. davidii Its sale is banned in Oregon and Washington, where it is considered a noxious weed. and many other states from coast to coast. Put it on their watch list. Only 20 states are currently not included in the list. B. davidii As a weed or invasive problem.
Although deadheading and weeding are helpful in reducing the potential spread of butterfly bush, plant feeders may be the answer to the problem. In recent years, numerous new seeds or hybrids with low fertility have come into the market.
“Sterile-Free” Butterfly Bush Varieties
In 2011, Oregon approved the sale of cultivars that produced 2 percent or less viable seed. Oregon prohibits these sterile hybrids from being called butterfly bush because the name is too closely associated in commerce. B. davidii. In Oregon, these plants should be labeled summer lilac, nectar bush, or seedless butterfly bush. The types listed below are considered sterile.
B. davidii ‘Asian Moon’
B. davidii ‘Miss Molly’
B. davidii ‘Miss Ruby’
Look and see® Series
A high performing sterile butterfly bush.
‘Purple Mist’ (pictured below) It is one of the only compact and sterile growers.® Series dark purple-blue flowers were produced frequently and continuously. Because the plant is sterile, all energy is put into making flowers instead of seeds. Its numerous flowers arch outward and downward over low spreading foliage. Its short, compact habit makes ‘Purple Haze’ perfect for massaging or as a ground cover. The genetic make-up of lo and behold® The series includes some species that are less suited to colder regions, so winter hardiness was on our minds. Unlike lo and behold® ‘Blue Chip’, which has died three winters in a row, ‘Purple Haze’ is reliably root-hardy.
—Richard Hauck is director of ornamental plant research at the Chicago Botanic Garden.
To see the results of the Chicago Botanic Garden’s plant trial on butterfly bush, go here.