Plant 396

Valeriana species (Caprifoliaceae)


The Latin valere, ‘to be healthy’, gives us the generic name Valeriana, a genus of 420 species, which includes annual and perennial herbs as well as subshrubs. The genus is widespread across much of Eurasia and the Americas, but is less frequent in Africa and Australia. The genus should not be confused with the so-called red valerian, which is a member of the genus Centranthus.

In the case of Valeriana officinalis, the Latin root of the name refers to the many medicinal roles assigned to it over several centuries. This clump-forming plant has bright green, pinnate leaves on stems, up to 1.5 m tall, topped by branched clusters of small, white flowers, which are attractive to pollinators such as hoverflies. These flowerheads are unusual in being completely asymmetrical. The part used in medicine is the dried, ground root., which has a peculiar and persistent smell that many people find unpleasant.

The supposed properties of valerian are various and sometimes contradictory, with uses dating back at least as far as Hippocrates (c.460-370 BCE). Mentioned in multiple influential medical works between 1733 and 1936, Valeriana officinalis was one of the five most prescribed medicines during this period. Herbalists such as John Gerard (c.1545-1612) and Nicholas Culpeper (1616-1654) note its uses as a general-purpose tonic, and list a vast range of unrelated ailments apparently responsive to valerian treatment – particularly for hysteria and similar conditions. It was used in Britain in the 1940s to reduce the stress of air raids, and was part of the US National Formulary until the 1950s.

Modern opinions on the medicinal value of Valeriana officinalis are divided. The European Medicines Agency has approved its use as a treatment for nervous tension and sleep disorders, but how effective it is in these roles remains unclear. Sedative effects have been demonstrated in mice, but studies on human insomniacs are, so far, too few and too methodologically flawed to provide reliable conclusions. Unfortunately, the chemistry and mechanisms of how valerian acts are unknown.

Valerian continues to be used as a home remedy for sleep problems. It is frequently found among the ingredients of ‘night-time teas’ on supermarket shelves, and in dietary supplements. Another area where it has attracted research attention is in animal welfare. As an alternative to the popular catnip (Nepeta cataria), Valeriana officinalis featured in a 2017 study of the use of plant species to enrich environments for domestic cats.

Bol, S et al. 2017. Responsiveness of cats (Felidae) to silver vine (Actinidia polygama), Tatarian honeysuckle (Lonicera tatarica), valerian (Valeriana officinalis) and catnip (Nepeta cataria). BMC Veterinary Research 13: 70

Grieve, M 1979. A modern herbal. Jonathan Cape, pp. 824-829.

Ruth Calder