Vervain, Blue

Verbena hastata is a hardy perennial that can be slow and uneven to germinate, but is otherwise straightforward to grow. For best results, seed should be cold-moist stratified before sowing, as this helps to break dormancy and improves germination rates.

Sow seed indoors in early spring. Prior to sowing, mix the seed with a small amount of moist sand, seal in a plastic bag, and place in the fridge for 2–3 weeks. After stratification, sow the seed on the surface of the compost and gently press it in; do not cover, as light helps to trigger germination. Keep the compost consistently damp but not waterlogged.

Germination can be slow and staggered, with seeds continuing to sprout over a long period — sometimes up to three months — so trays should not be discarded prematurely.

Once seedlings are large enough to handle, prick out into individual pots and grow on until well established before planting out. Allow a spacing of around 45–60cm between plants. Verbena hastata prefers moisture-retentive soil and grows well in full sun or partial shade, making it particularly suited to damp areas of the garden.

Plants usually produce leafy growth in the first year, followed by tall spires of purple flowers in mid to late summer in subsequent years.

Whilst blue vervain – indigenous to America – has similar therapeutic activity to its relative Verbena officinalis, the European vervain, it looks very different. Its magenta-blue flowers grow to eye height by mid-Summer luring the eye and bees towards them.

Favoured for use in the Native American tradition, it was later written about by the famous Eclectic physicians Harvey Felter and John Uri Lloyd in King’s American Dispensatory and William Cook’s Physiomedical Dispensatory where it is considered a ‘relaxant tonic’. It has a bitter and astringent flavour that can cool a hot head and a hot liver. It is used as an anxiolytic nervine for acute and chronic stress leading to spasms, cramps and tension making it useful for headaches, digestive stagnation, nervous tics and muscle spasms. As it helps smooth the flow of the emotions it can dissipate irritability and digest indigestible experiences, helping mild depression. Its especially relevant for symptoms of menstrual anxiety and cramps and menopausal heat and anxiety, but its not to be used in pregnancy.

It goes well with motherwort, skullcap and lemon balm for anxiety and with tonics like ashwagandha and milky oatseed for nervous exhaustion.

Harvest the aerial parts just as it comes into flower, avoiding any discoloured lower leaves. Then immediately cut into smaller pieces and dry by laying out on an open rack or, even easier, tie the stems into bunches and hang upside down to dry.

As a tea, use 1-2 teaspoons (1.5-3g) in a cup of boiled water steeped for 15 minutes a couple of times a day.

To make a tincture infuse 1 part herb to 5 parts with the alcohol @ 40%.