Physostegia virginiana

RHS Plant Profile
obedient plant

Other common names

accommodation flower, American heather, lady of the lake, lion's heart, lion's mouth, Mexican heath, obedient flower, pink shellflower, St Margaret's flower, toad's mouth, Virginian false dragon's head

Synonyms

Dracocephalum virginicum

Herbaceous Perennial

An herbaceous perennial to 1m tall, with erect, square stems bearing lance-shaped, toothed leaves. From midsummer to early autumn it produces purple to pink (occasionally white) tubular flowers, held in short, upright spikes; the flowers are good for cutting. The common name refers to individual blooms, which will stay in position if moved around on their stalks

Position

Full sun, Partial shade

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
0.5-1 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained
pH
Acid or Alkaline or Neutral

Position

Full sun Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Sheltered
Hardiness
H7

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Lamiaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Clump forming
Genus
Physostegia are erect rhizomatous herbaceous perennials with neatly arranged pairs of toothed leaves and terminal racemes of 2-lipped, tubular flowers in summer
Name Status
Correct
Plant Range
North America

How to Grow

Cultivation

Grow in fertile, reliably moist soil in full sun or partial shade

Propagation

Propagate by sowing seed in containers in a cold frame in autumn, or by division in early spring

Suggested planting locations and garden types

  • Coastal
  • Cottage and informal garden
  • Cut flowers
  • Flower borders and beds

Pruning

Cut back old stems in winter

Pests

May be susceptible to slugs and snails

Diseases

May be susceptible to fungal and bacterial rots