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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:
This plant will provide nectar and pollen for bees and the many other types of pollinating insects.
It is included in an evolving list of plants carefully researched and chosen by RHS experts. Divided into 3 groups these lists, linked below, are maintained by a team of RHS staff and are reviewed annually.
the RHS today and get 12 months for the price of 9
Other common names
bois chavanon catawba
cigar tree early-flowering catalpa hardy catalpa northern catalpa Indian cigar shawnee wood western catalpa
Catalpa are deciduous trees of spreading habit, with handsome, large leaves and erect panicles of showy, bell-shaped flowers in late summer, followed by persistent, slender bean-like seed capsules
C. speciosa is a tall, spreading tree with large, heart-shaped leaves. Large purple-spotted, white flowers sparsely borne in July, followed by long, slender seedpods
Habit Spreading / Branched
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 West-facing or East-facing
MoistureMoist but well-drained
SoilChalk, Clay, Sand, Loam
pHAcid, Alkaline, Neutral
Higher than 12 metres
wider than 8 metres
Time to ultimate height
Grow in a moist but well-drained, fertile soil in a sunny position; will tolerate a heavy clay soil. Shelter from strong winds as these may shred the large leaves. Protect from late spring frosts when young
Propagate by softwood cuttings or grafting
Suggested planting locations and garden types
Pruning Pruning group 1 or Pruning group 7 if grown pollarded
Pests Generally pest free
Susceptible to verticillium wilt
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
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