Ballota nigra L.
Ballota nigra L. also known as Stinking Horehound (because it does) belongs to the Labiatae family (hence the square stem). This hairy plant is a native British herb common on roadsides and hedgebanks growing up to a metre high. The orbicular, petiolated leaves (2-5cm) are coarsely crenate. The pale purple flowers, with funnel shaped calyces, sit as grouped whorls in the leaf axils and are pollinated by bees. Some of its constituents include the diterpenes (“bitter principles”) ballotenol and ballotinone; flavonoids and volatile oil. As well as its anti-emetic effect it is mildly astringent and sedative indicated specifically to help vomiting of a central origin (therefore during pregnancy) or nausea and nervous dyspepsia.