Common vervain

Common vervain: how do you recognise it?

Habit

Upright, branching plant 40–80 cm tall and 30 cm wide, short-lived (sometimes biennial).

Stem

Square, rough and stiff, branching in the upper half.

Leaves

Deeply cut to pinnately lobed at the base, smaller and three-parted higher up; rough to the touch, grey-green.

Flower

Tiny lilac flowers (3–4 mm) in long, slender spikes at the shoot tips, from June to September.

Roots

A taproot with side roots: it tolerates drought, but not soil that is too wet.

Flowering: June–September · Harvest and fruit: July–August · Sowing: April–May · Plants: April–May · Pruning: March and September

Why grow it?

• A native plant that suits a wild, insect-friendly garden.
• Long flowering from June to September, when many other plants have finished.
• Slender, airy spikes that float around other plants and give a border a light, playful look.
• Undemanding: it grows on poor, dry soil in full sun.
• The leaf can be used for tea, with a slightly bitter taste.

Common vervain: where does it grow best?

• Full sun in a warm, open spot.
• Free-draining, poor to moderately fertile soil: sand, loam or clay, neutral to chalky.
• Dry to normally moist; standing water is harmful, especially in winter.
• Plant 30 cm apart; sow it among other plants for a natural effect.

Light

Sun

Soil type

Sand, loam or clay

Acidity

Not fussy

Moisture

Dry or normal

Size

0.6 m tall, 0.3 m wide

Hardiness

Hardy (to -25 °C)

Goes well with

• Yarrow: The same sunny, dry spot; the flat heads contrast with the slender spikes.
• Wild marjoram: A fragrant perennial that attracts bees and butterflies.
• Common knapweed: Native pinkish-purple flowers beside the lilac spikes.
• Oxeye daisy: White flowers that suit a wild, dry border.

Common vervain: when and how to plant it?

Plant in April–May.

1. Sow in April–May directly outside in a sunny spot; the seeds germinate slowly and unevenly, and a cold spell helps: sowing in October–November also works.
2. Scatter the seeds on loose, finely raked soil and barely cover them (they germinate in light).
3. Or plant young plants in April–May 30 cm apart, at the same depth as in the pot.
4. Firm the soil gently and water.
5. Thin the seedlings to 30 cm once they are large enough.

Care

Water

In the first year, water in dry spells. After that it looks after itself.

Feeding

Not needed: in rich soil it becomes floppy and falls over.

Self-seeding

It seeds itself readily. Leave a few spikes for next year, or cut them off if you do not want that.

Maintenance

Keep the soil around young plants free of weeds; later it grows through its neighbours.

Harvesting

Pick leaves and flower tops in July–August for tea and dry them in an airy, shady place.

Tip: Sow it in a sunny, poor spot: it will then seed itself. In September, cut off faded spikes if you want to limit self-seeding.

Common vervain: when to prune it?

Pruning months: March and September.

When: In March, cut away the old stems; in September, cut off faded spikes if you want to limit self-seeding.

How:

• Leave the dry stems and seeds standing in winter: they look good and feed birds.
• In late February–March, cut all stems back to just above the ground.
• If you do not want self-seeding, cut off the faded spikes in September before the seeds ripen.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

Sow in April–May or October–November directly outside, barely covered. The seeds germinate slowly and unevenly.

Self-sown seedlings

It seeds itself: move young seedlings in spring to where you want them.

Common vervain: how does it get through the winter?

Hardy to −25 °C.

• Fully hardy to about −25 °C: no protection is needed in Belgium.
• The top growth dies back in winter; the plant shoots again in spring or returns from seed.
• In a pot: keep the pot sheltered from rain so the roots do not rot.

Diseases and pests

• Powdery mildew: White powder on the leaves in dry or humid late summers. Give more space and cut away affected leaves.
• Floppy and falling over: In rich soil or partial shade. Plant it in more sun and do not feed.
• Root rot: In wet, heavy soil in winter. Provide free-draining soil or mix in sand.
• Aphids: On young shoots. Rinse off with water or let ladybirds clear them.

Through the year

• March: Cut the stems back to just above the ground.
• April: Sow or plant. Move self-sown seedlings.
• May: Sow or plant. Thin seedlings to 30 cm.
• June: Flowering begins.
• July: Flowering. Harvest leaves and flower tops for tea.
• August: Flowering: bees and butterflies visit.
• September: Last flowers. Cut off faded spikes to limit self-seeding.
• October: You can still sow in autumn.

Edible and useful

Leaves (July–August)

Cut the flowering stems in July and August, on a dry morning, a hand’s breadth above the ground: leaves and flower spikes together. Common vervain has hardly any scent and tastes bitter. Use it fresh or dried for herbal tea, preferably mixed with something fresh such as mint or lemon verbena. Do not confuse it with lemon verbena (Aloysia citrodora), the lemon-scented shrub used for the familiar verveine tea in France: common vervain is a native herb with tiny lilac flowers and no lemon scent.

Storing

Tie the stems in small bunches and hang them upside down somewhere airy and shady. After one to two weeks, once they are crisp, cut them into pieces of 1 to 2 cm. Keep them dry and dark in a closed jar: that way they keep for a year.

Caution: Drink vervain tea in moderation: one or two cups a day at most, and not for weeks on end. In large amounts it can make you feel sick. Not during pregnancy or breastfeeding, nor for young children. It is an old medicinal herb, not a medicine: if symptoms persist, see a doctor.

Eating and using is at your own risk: see the terms of use.

Recipes

• Vervain tea (Tea · 1 cup · 10 min)
• Tea blend with vervain, lemon verbena and mint (Tea · ± 25 cups · 10 min)

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• The name verbena goes back to the Latin word for sacred branches, which the Romans used in rituals.
• Lemon verbena (Aloysia citrodora) belongs to the same family, the Verbenaceae, but is a quite different plant.
• In old folk tales it was regarded as a magic herb.