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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
Cosmos can be annuals or perennials with simple or pinnately divided leaves and large, long-stalked daisy-like flowers in summer
C. sulphureus is a half-hardy annual with fresh, fern-like foliage and a long flowering season. Selections are variable in height, most between 50cm and 1m, but including some dwarf forms. Flower colour is varied, in many tones of yellow, orange and red
Mexico, C America, N S America
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
MoistureMoist but well-drained
SoilSand, Chalk, Loam
pHAcid, Alkaline, Neutral
Time to ultimate height
Grow in moderately fertile, moist but well-drained soil in full sun
Propagate by seed in mid spring
Suggested planting locations and garden types
Cut Flowers Flower borders and beds
City & Courtyard Gardens Cottage & Informal Garden Sub-tropical
Pruning Deadheading should be carried out regularly to prolong flowering
Pests Aphids and slugs may be a nuisance
grey mould may be a problem
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