Common Name: American Blue Vervain

General Information

Verbena hastata is a herbaceous perennial plant, growing from a spreading rhizomatous rootstock.It grows 60 - 150cm tall, producing a slowly-spreading cluster of erect stems that branch above[].
The plant is harvested from the wild for local use as a food and a medicine. It is sometimes grown as an ornamental in gardens[].

Known Hazards

Blue vervain can interfere with blood pressure medications and hormone therapy[].
Large doses will induce vomiting and diarrhoea[].

Botanical References

,

Range

N. America - British Colombia to Quebec and Nova Scotia, south to California, Texas and Florida

Habitat

Swales, damp thickets and shores[]. Moist meadows, thickets, and pastures, as well as riversides, marshes, ditches, and river-bottom prairies[].

Properties

Edibility Rating
Medicinal Rating
Habit	Perennial
Height	1.50 m
Pollinators	Bees, Flies, Lepidoptera, Self
Self-fertile	Yes
Cultivation Status	Ornamental, Wild

Cultivation Details

Verbena hastata is hardy to about -20°c[].
Succeeds in any moderately fertile well-drained but moisture retentive soil in a sunny position[, ]. Often found in wet soils in the wild[].
Plants may self-seed freely in gardens in optimum growing conditions[].

Edible Uses

Seed - cooked[]. The seed can be roasted and ground into a powder or used whole as a piñole[, , , ]. Pleasantly bitter, some of this bitterness can be removed by leeching the flour[].

The leaves are used as a tea substitute[, , ].

Medicinal

The leaves and roots are antiperiodic, diaphoretic, emetic, expectorant, tonic, vermifuge and vulnerary[, , , ]. The roots are more active than the leaves[].
The plant is used in the treatment of stomach aches, gravel, worms and scrofula[, ]. It is taken internally to treat depression, fevers, coughs, cramps, jaundice, and headaches[].
Applied externally, it is used in the treatment of acne, ulcers, and cuts[].

An infusion of the roots, leaves or seeds has been used in the early stages of fevers[].

A snuff made from the dried flowers has been used to treat nose bleeds[].

Other Uses

None known

Propagation

Seed - sow autumn in a sunny position greenhouse or cold frame and only just cover the seed[]. Stored seeds should be stratified before sowing by storing in a sealed, container or plastic bag with wet sand or peat moss at 3 - 5°c for three month. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer.
Division in spring. Larger divisions can be planted out direct into their permanent positions. We have found that it is best to pot up smaller divisions and grow them on in light shade in a greenhouse or cold frame until they are growing away well. Plant them out in the summer or the following spring.
Basal cuttings in early summer. Harvest the shoots with plenty of underground stem when they are about 8 - 10cm above the ground. Pot them up into individual pots and keep them in light shade in a cold frame or greenhouse until they are rooting well. Plant them out in the summer.