Argentina Vervain

How to grow Argentina Vervain

Written by the GardenDecoded editorial team · Last reviewed 21 July 2026 · Written for UK gardens · How we research our guidance

Planting

Plant in spring after the worst of the frosts, in an open sunny position on soil that drains freely. The stems are thin and see-through, so it can go at the front of a border as well as the back without blocking the view. Plant in drifts rather than singly.

Pruning

Leave the top growth on over winter — it gives some frost protection to the crown as well as looking good — and cut back to about 15 cm in early spring once new shoots appear at the base. Deadheading is not necessary and reduces the seed for birds.

Propagation

Self-sows readily in gravel and open soil, and transplanting seedlings in spring is the simplest method. Softwood cuttings in early summer root easily and are a useful insurance against a hard winter.

Pests and diseases

Powdery mildew is the most common issue, especially in a dry summer or where air movement is poor. Slugs take the young spring growth.

Value to wildlife

One of the best late-season nectar plants in British gardens — butterflies, bees and moths work it heavily from midsummer into autumn.

Notes

Short-lived, and a wet cold winter on heavy soil will often kill it outright. In practice it survives in gardens by seeding itself, so leave some seedlings and do not weed the gravel too keenly.

This guidance was researched and written by GardenDecoded — see our editorial policy for how guides are checked and reviewed.

Other names for this plant

These names have all been used for Verbena bonariensis but are no longer the accepted name. You may still meet them on old labels, in books, or in nursery catalogues.

Others in Verbena