Verbena Rigida, Slender Vervain

• Variety: Slender Vervain
• Latin name: Verbena rigida, syn. Verbena venosa
• Type: Tuberous perennial
• Flower: Fragrant clusters of vivid purple
• Height: 60cm (2ft)
• Spread: 45cm (18in), spreading gently by rhizomes
• Flowering: July to October
• Position: Full sun, any well-drained soil, thrives on chalk
• Hardiness: Borderline hardy (RHS H3): fine in mild, drained gardens, mulch or lift elsewhere
• Pruning: Cut to the ground in early spring when new shoots show
• RHS AGM: Yes, it holds the RHS Award of Garden Merit
• Wildlife: On the RHS Plants for Pollinators list
• Sold as: 2L pot-grown plants
• Plant outdoors: After the last frost, and any time through summer
• Delivered: Year round. Collection from Castle Cary also available

Purpletop's knee-high cousin: the same electric purple, brought down to the front of the border and kept flowering until the frosts.

Verbena Rigida: The Knee-High Vervain

Verbena rigida, the slender vervain, is a tuberous perennial around 60cm tall that carries dense, fragrant clusters of vivid purple from July to October. It holds the RHS Award of Garden Merit and sits on the RHS Plants for Pollinators list, both earned: on a warm September afternoon the flowers work as hard as a buddleia, drawing bees, butterflies, moths and hoverflies until the light goes.

Most gardeners know its tall relative already. Purpletop Vervain is the see-through 1.5m one for the back; rigida is the same saturated purple at knee height, denser, stiffer, made for the front edge, gravel gardens and pots. (The frost-tender trailing verbenas sold for hanging baskets are a different thing entirely; don't judge this plant by them.) One plant becomes a drift over a couple of seasons, spreading gently by rhizomes and a little self-seeding, all of it easy to edit with a trowel.

Hardiness, handled honestly: this is an H3 plant, South American by birth, which explains both the marathon flowering and the dislike of wet feet. In mild or coastal gardens with sharp drainage it comes through winter under a deep, dry mulch. In cold gardens or heavy soil, lift the roots after the first frosts; they're pencil-thin tubers, so you store them exactly like dahlias, in barely damp sand somewhere frost-free, and replant the clumps you recieve back from storage after the last frost. Winter wet is the killer, not cold alone.

Planting Partners for Verbena Rigida

The purple flatters warm colours, so let Echinacea Cheyenne Spirit throw its oranges and scarlets around it at the same height. Hidcote lavender shares the sun, the drainage and the bee traffic along a path edge. And because rigida wakes late in spring, plant tulips among the crowns: they flower and fade before the vervain needs the space.

Why Ashridge?

We list Verbena rigida as an H3 plant and say so plainly, with the two overwintering routes on this page rather than in the returns process. Your plants arrive in 2L pots ready to flower this season, grown peat-free, and guaranteed like everything we sell.

Frequently Asked Questions

Is Verbena rigida hardy?

Borderline: it's rated H3, reliable outdoors through winter only in mild gardens with sharp drainage. Elsewhere, mulch the crown deeply in late autumn or lift and store the tubers like dahlias. Drainage is the whole game.

What is the difference between Verbena rigida and Verbena bonariensis?

Height and placement. Bonariensis is the airy, see-through one at 1.5m for the middle or back; rigida is denser and richer purple at 60cm for the front. Same border, two storeys; we grow both.

Will Verbena rigida spread?

Gently, yes: it creeps by rhizomes and self-seeds a little, so a single plant becomes a drift within two or three seasons. Unwanted pieces pull out easily in spring, so it never becomes a thug.

Is Verbena rigida the same as Verbena venosa?

Yes. Verbena venosa is simply the old name for Verbena rigida, and some nurseries and older books still use it. Same plant, same purple, same tuberous roots.

How do I overwinter Verbena rigida?

Two routes. In free-draining soil, cut nothing back and lay a deep, dry mulch over the crown at the start of winter. In cold or heavy gardens, lift the tubers after the first frosts and store them frost-free in barely damp sand; pots can just move somewhere dry.

When should I cut back Verbena rigida?

In early spring, once new shoots show at the base; never in autumn. The old top growth is part of the plant's winter protection, and cutting it early invites the wet into the crown.