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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
round-headed garlic round-headed leek
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
A. sphaerocephalon is a tall perennial with a tuft of narrow basal leaves to 30cm long, and long-stalked, dense, rounded heads of pink or reddish-brown flowers in 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 North-facing or West-facing or East-facing
MoistureWell-drained, Moist but well-drained
SoilSand, Clay, Chalk, Loam
pHAcid, Alkaline, Neutral
Time to ultimate height
Easy to grow in fertile well-drained soil. Add grit when grown in clay soils to improve drainage
Propagate by seed, sowing in containers in a cold frame when just ripe or in the spring. Alternatively, remove offsets in autumn
Suggested planting locations and garden types
Flower borders and beds
City & Courtyard Gardens Coastal Cottage & Informal Garden Patio & Container Plants
Pruning No pruning required
Pests Generally pest free
Onion white rot and a downy mildew may occur
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
Buy from £5.98 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