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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
the RHS today and get 12 months for the price of 9
Other common names
great blue-bottle mountain bluet
mountain centaury perennial cornflower
Centaurea may be annuals, perennials or subshrubs, with simple or pinnately lobed leaves and showy thistle-like flowers-heads, often with enlarged outer florets
C. montana is a rhizomatous perennial with simple or lobed leaves, hairy beneath, and blue flower-heads 5cm across, reddish in the centre, from late spring to summer
Mts of Europe
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 North-facing or East-facing or West-facing
Exposure Exposed or Sheltered
MoistureMoist but well-drained
SoilLoam, Chalk, Sand, Clay
pHAcid, Alkaline, Neutral
Time to ultimate height
Best grown in moist but well-drained soil in sun or partial shade, needs staking
Propagate by seed sown in pots in a cold frame in spring or propagate by division in spring or autumn
Suggested planting locations and garden types
Flower borders and beds Cut Flowers
Cottage & Informal Garden Wildlife Gardens Prairie Planting Coastal
Pruning Deadhead regularly to prolong flowering
Pests Generally pest free
May be affected by powdery mildews
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