Persicaria microcephala
small-headed knotweed
A dense, rhizomatous herbaceous perennial with distinctively-patterned, reddish to dark green oval foliage with distinctive brown and grey markings which are held on short, winged stalks. Small, rounded heads of tiny white or pinkish flowers top branching stems to 60cm high, from midsummer to autumn
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
1.5–2.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green Grey Silver Purple | |||
|---|---|---|---|---|
| Summer | Pink White | Green Grey Silver Purple | ||
| Autumn | Pink White | Purple | ||
| Winter | Bronze |
Position
- Full sun
- Partial shade
Aspect
West–facing or South–facing or East–facing
Exposure
Exposed or Sheltered Hardiness
H5Botanical details
- Family
- Polygonaceae
- Native to GB / Ireland
- No
- Foliage
- Semi evergreen
- Habit
- Trailing
- Genus
Persicaria can be annuals, herbaceous or evergreen perennials or sub-shrubs with simple leaves and small bell-shaped white or pink flowers in long-lasting spikes or panicles
- Name status
Correct
- Plant range
- SE Asia
How to grow
Cultivation
Grow in well-drained or moisture retentive soil in sun or part-shade. Dense groundcover, but has the potential to become a nuisance if not managed well
Propagation
Propagate by seed in spring, or propagate by stem tip cuttings of non flowering shoots or by division
Suggested planting locations and garden types
- Cottage and informal garden
- Coastal
- Wildflower meadow
- Banks and slopes
- Flower borders and beds
- Ground cover
Pruning
Cut back in autumn
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.