Verbena officinalis, the common vervain or common verbena, is a perennial herb native to Europe. It grows up to a metre/yard high, with an upright habitus. The lobed leaves are toothed, the delicate spikes hold mauve flowers.
A sweet and delicate musk-like odour is produced by the seed coat. The essential oil obtained from the plant is used as a food flavouring and in perfumery...
The fruits are a conical pod with seeds contained in holes in the pod. When the seeds are ripe, they become loose in the pod. The pod then tips down towards the water, releasing the seeds.