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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
bachelor's buttons cornflower
barbeau blaver blawort blue blaw blue bonnets bluebottle blue bow blue poppy blue sailors blue tops bluets break-your-spectacles brushes bunk corn binks cornbottle corn centaury French pink happy skies haw dods hurtsickle ragged robin ragged sailor witches' bells
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. cyanus is an upright annual to 75cm, with simple or slightly lobed leaves and solitary deep blue flower-heads 3-4cm across in late spring and summer
N temp. regions
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
Exposure Sheltered or Exposed
pHNeutral, Acid, Alkaline
Time to ultimate height
Grow in well-drained soil in full sun
Propagate by seed sown in-situ in spring
Suggested planting locations and garden types
Flower borders and beds Cut Flowers
Patio & Container Plants Coastal Wildflower meadow Wildlife Gardens
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.
Buy from £2.49 at the RHS Plants Shop
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