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We have combined these two powerful search tools into a single Find a Plant service searching over 250,000 plant records.
Virtually all of the features of the old searches are still available and in addition we have added several new features to create a more comprehensive and user friendly search experience.
When using this search
Search by plant name, key attributes or both to find plant details and a list of
AGM plants have been through a rigorous trial and assessment programme. They are:
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Other common names
knotweed 'Darjeeling Red'
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
'Darjeeling Red' is 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
Habit Mat forming
Toxicity Contact with all parts may irritate skin
All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets
Aspect South-facing or North-facing or West-facing or East-facing
Exposure Exposed or Sheltered
MoistureMoist but well-drained, Poorly-drained, Well-drained
SoilClay, Loam, Sand, Chalk
pHAcid, Alkaline, Neutral
Time to ultimate height
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
Propagate by division in spring or autumn, or stem-tip cuttings of non flowering shoots
Suggested planting locations and garden types
Flower borders and beds Garden Edging Ground Cover
City & Courtyard Gardens Coastal Cottage & Informal Garden Gravel Garden Rock Garden Patio & Container Plants
Pruning No pruning required but remove spent flowers if necessary and comb out old leaves
Pests Generally trouble free
Generally trouble free
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Join the RHS today and get 12 months for the price of 9