Lythrum flowers

Upright, bushy herbaceous perennials with dense spikes of showy flowers. Ideal for a moist border or bog garden.

Family: Lythraceae
Botanical Name: Lythrum (lith-rum)
Common Names: Loosestrife, long purples

Foliage: Deciduous mid-green, simple narrow leaves.

Flowers: Tall spikes of small purplish-pink flowers.

Flowering Period: Mid-summer to early autumn.

Soil: Moist, poorly drained soil (clay or loam). Acid, alkaline or neutral pH.

Conditions: Full sun or partial shade. Plant in an east or south facing aspect.

Habit: Upright, bushy.

Type: Herbaceous perennial.

Origin: Europe, Asia

Hardiness: Hardy in the UK.

Planting and Growing Lythrum

Easy to grow. Plant at any time during the dormant season. Grow in full sun or partial shade. Best planted in an open sunny site but will tolerate dappled shade. Thrives beside a pool or stream in damp to wet soil.

Ideal for cottage, informal or wildlife gardens.

Good source of cut flowers.

Taking Care of Lythrum

Water well in dry weather. Apply a good top dressing of organic matter (leaf-mould or compost) annually, in the autumn or spring. Divide every three or four years to rejuvenate.

Pruning Lythrum

Tidy up the plants in autumn. Can be invasive, so cut down stems after flowering to prevent self seeding.

Pests and Diseases

Susceptible to attack by slugs and snails.

Propagating Lythrum

Divide established clumps when dormant. It is also possible to propagate by semi-ripe cuttings in midsummer and keep shaded in a coldframe

Popular Varieties of Lythrum

Lythrum salicaria (purple loosestrife) is a vigorous hardy perennial with attractive small leaves and dense terminal spires of reddish-purple flowers, summer to autumn. Height up to 5ft (1.5m), spread 3ft (1m). Varieties include:

  • 'Brilliant' pink flowers.
  • 'Firecandle' intense red flowers on slender spikes in summer.
  • 'Lady Sackville' rose-pink flowers.
  • 'Rose Queen' and 'Robert' pink flowers.
  • 'Robin' beautiful magenta pink blooms. Height: 36in (90cm), spread: 18in (45cm). For sale at Thompson & Morgan.
  • 'The Beacon' deep carmine-red flowers.

Lythrum virgatum (Turkey) is a more slender and compact plant with spires of purple flowers in June-August. Height and spread 2-3ft (60-90cm). Useful where space is limited. Varieties include:

  • 'Dropmore Purple' slender graceful spikes of rosy-purple flowers in early to late summer. Height 2.5ft (75cm).
  • 'Rose Queen' fine bright rose-red spikes of flowers, late summer and autumn. Height 1.5 to 2ft (45 to 60cm).
  • 'The Rocket' stiff erect, narrow graceful spikes of deep pink flowers. Height 3ft (90cm).