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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:
the RHS today and get 12 months for the price of 9
Other common names
dahlia 'Witteman's Superba'
Dahlia are tuberous rooted perennials with pinnately divided leaves and showy flower-heads, double in many cultivars, in summer and autumn
Semi-cactus dahlias have fully double flowerheads with narrow, pointed, straight or incurved ray florets broader at the base
'Witteman's Superba' grows to 1.3m in height, with deep crimson flowers 15cm in width from late summer
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 East-facing
MoistureMoist but well-drained
SoilLoam, Clay, Sand
pHAcid, Neutral, Alkaline
Time to ultimate height
Grow in fertile, humus-rich, well-drained soil, enriched with organic matter and general purpose fertiliser, in full sun. Pinch out growing tips to encourage bushy plants and stake. Water freely in dry periods. Lift and store tubers in autumn to replant or use as a source of cuttings in spring
Propagate by softwood cuttings taken in spring from shoots from stored tubers, or divide the tubers ensuring each division has a viable bud
Suggested planting locations and garden types
Flower borders and beds Cut Flowers
City & Courtyard Gardens Cottage & Informal Garden Patio & Container Plants
Pruning Deadhead to prolong flowering. Cut back to near ground level in the autumn, before lifting and storing for the winter
Pests Aphids, leaf miners, glasshouse red spider mite and slugs are common pests. Earwigs sometimes damage blooms. Capsid bug and caterpillars are occasional pests
Powdery mildews can be damaging in dry conditions. In wet weather grey moulds and other fungal rots can be a problem. Fungal rots can also damage stored tubers. A virus may cause stunting, leaf markings and distortion
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
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Join the RHS today and get 12 months for the price of 9