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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
Allium are bulbous herbaceous perennials with a strong onion or garlic scent, linear, strap-shaped or cylindrical basal leaves and star-shaped or bell-shaped flowers in an umbel on a leafless stem
'Millennium' is a clump-forming perennial to 40cm, with thick, narrow leaves and 5cm pompoms of rose-pink, star-shaped flowers on upright stems in mid-to late summer
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 Exposed or Sheltered
SoilSand, Chalk, Loam
pHAcid, Alkaline, Neutral
Time to ultimate height
Grow in reasonably fertile, well-drained soil with full sun. The leaves generally die down before the flowers open. See allium cultivation advice
Propagate by division in early spring
Suggested planting locations and garden types
Flower borders and beds
City & Courtyard Gardens Cottage & Informal Garden Gravel Garden Patio & Container Plants
Pruning No pruning required
Pests May be affected by onion fly
May be affected by onion white rot and downy mildew and occasionally leek rust
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
Buy from £12.99 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.