Persicaria affinis 'Darjeeling Red'

RHS Plant Profile
knotweed 'Darjeeling Red'

Synonyms

Persicaria affinis 'Darjeeling Red'
Polygonum affine 'Darjeeling Red'

Award of Garden Merit
Alpine Rockery Herbaceous Perennial

A semi-evergreen perennial to 25cm tall, forming a mat of lance-shaped leaves to 15cm long, often becoming red in autumn; in summer dense spikes of small flowers open pink, becoming dark red when mature

Position

Full sun, Partial shade

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.1-0.5 metres

Max Spread

0.1-0.5 metres

Size

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

Growing Conditions

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

Position

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

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Polygonaceae
Native to GB/Ireland
No
Foliage
Semi evergreen
Habit
Matforming
Genus
A genus of herbaceous, rhizomatous perennials with erect, unbranched stems, bearing short terminal spikes of small, white or pink, bell-shaped flowers
Name Status
Accepted

How to Grow

Cultivation

Prefers moisture retentive soil in sun or part shade but may spread quickly in wet soil. It is tolerant of dry and light soils in sun or shade where it will spread more gradually See https://www.rhs.org.uk/plants/trials-awards

Propagation

Propagate by division in spring or autumn, or stem-tip cuttings of non flowering shoots

Suggested planting locations and garden types

  • City and courtyard gardens
  • Coastal
  • Cottage and informal garden
  • Gravel garden
  • Patio and container plants
  • Rock garden
  • Garden edging
  • Flower borders and beds
  • Ground cover

Pruning

No pruning required but remove spent flowers if necessary and comb out old leaves

Pests

Generally pest-free

Diseases

Generally disease-free