Bistorta affinis 'Darjeeling Red'
knotweed 'Darjeeling Red'
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
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Poorly–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Pink Red | Green | ||
| Autumn | Pink Red | Green | ||
| Winter | Green |
Position
- Full sun
- Partial shade
Aspect
South–facing or East–facing or North–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H7Botanical 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
Get involved
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.