Morden Pink Loosestrife, a member of the loosestrife family to which crape myrtle belongs, is a semi-woody perennial that grows to four feet in height and has willow-like leaves two to four inches long. In midsummer it produces 1-inch wide pink flowers crowded onto an upright spike that’s 6-8 inches long.

Morden Pink, developed by Dr. Skinner at the Agricultural Research Station in Manitoba, Canada, has been marketed since 1937 as a male sterile sport that’s not supposed to set seed. Apparently, when grown in isolation by itself, it is seedless (if it really is the original strain); but when pollinated by other related species, it too will bear seed.