Leonurus cardiaca Motherwort
Native to Central Asia and south-eastern Europe, this member of the Mint family has a long history of medicinal use. Its leaves have three distinctive lobes with pointed tips and diminish in both length and lobe size in the upper parts of the plant. Whorls of small, sessile, pink-lilac flowers with tubular, two-lipped corollas bloom from July to September in rosettes nestled in the leaf axils. Height 1 metre. Part sun in moisture retentive soil.