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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
knapweed 'John Coutts'
Centaurea may be annuals, perennials or subshrubs, with simple or pinnately lobed leaves and showy thistle-like flowers-heads, often with enlarged outer florets
'John Coutts' is a vigorous herbaceous perennial, with jagged lobed leaves white-felted beneath, and showy purplish-pink flower-heads 6cm across in summer and often into early autumn
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
Time to ultimate height
Grow in well-drained soil in full sun. Attractive to bees and butterflies
Propagate by seed in containers in a cold frame in spring. Propagate by division in spring or autumn
Suggested planting locations and garden types
Flower borders and beds
City & Courtyard Gardens Coastal Cottage & Informal Garden Wildlife Gardens
Pruning No pruning necessary
Pests Generally trouble free
Powdery mildews may occur
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.