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Thursday - July 17, 2008

From: Pleasant Hill, MO
Region: Midwest
Topic: Butterfly Gardens
Title: Deadheading flowers on hybrid Black Knight butterfly bush
Answered by: Barbara Medford


I have two Black Knight Butterfly bushes in my landscape. Should I deadhead the flowers on this bush? Also, should I prune this back, if so, when, how much? I live near Kansas City, Missouri.


Just about any plant is going to benefit from being deadheaded, unless you are planning to take seed. And, taking seed from a highly hybridized plant like Black Knight would be of little use, as the seed would probably not breed true to the hybrid characteristics. Hybrids are nearly all propagated by softwood cuttings. Those who grow this plant recommend deadheading as it will encourage more blooms. And if it begins to get out of bounds, don't be afraid to prune it back so it doesn't try to take over your garden. In Missouri, you would probably be wise to cut your plant back to about 6 inches from the ground in late winter. This should help it to come back more vigorously than ever. Read this article on the culture of the Black Knight from your own Missouri Botanical Garden website.

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