I love growing butterfly bushes, and wanted to a deep, dark purple
"Black Knight" to my collection. We went to a nursery that had a few
in bloom, but not the size we wanted. So we purchased a smaller plant
that wasn't in bloom. When it finally did bloom, it wasn't the deep
almost black purple, but more of a bright purple. Might my plant get
darker flowers with age, or should I return the plant?