Persicaria microcephala
small-headed knotweed
Densely covers the ground with distinctively-patterned ,reddish to dark green foliage spreading from stout rhizomes. The broadly oval leaves with distinctive brown and grey markings 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 the UK
- No
- Foliage
- Semi evergreen
- Habit
- Trailing
- Potentially harmful
- Contact with all parts may irritate skin, the sap may cause mild stomach upset if ingested. Wear gloves and other protective equipment when handling
- 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
How to grow
Cultivation
Grow in well-drained or moisture retentive soil in sun or part-shade. Dense groundcover, can be invasive so needs careful siting
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
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