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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.
© RHS 2002
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Other common names
Bengal clock vine blue skyflower
blue trumpet vine clock vine skyflower sky vine
Thunbergia can be annuals or perennials, often twining climbers, with simple opposite leaves and trumpet-shaped or salver-shaped flowers borne singly in leaf axils, or in racemes, in summer
T. grandiflora is a very vigorous twining evergreen shrub to 6m or more, with heart-shaped, coarsely-toothed leaves and racemes of trumpet-shaped, light violet-blue flowers 7cm across, yellow in the throat
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
pHAcid, Alkaline, Neutral
Time to ultimate height
Grow under glass in a loam-based potting compost in bright filtered light with shade from hot sun. When in growth water moderately and apply a balanced liquid fertilizer monthly. Water sparingly at other times
Propagate by seed or softwood cuttings
Suggested planting locations and garden types
Patio & Container Plants
Pruning Pruning group 11
Pests May be attacked by glasshouse whitefly, glasshouse red spider mite, aphids and scale insects when grown under glass
Generally disease free
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.
Join the RHS today and get 12 months for the price of 9