Help us achieve our goals:
make a donation »
Join the RHS today and
support our charity
Free personalised gardening advice
RHS members get reduced ticket prices
RHS members get free access to RHS Gardens
Reduced prices on RHS Garden courses and workshops
020 3176 5800
Mon – Fri | 9am – 5pm
Make a donation
Join the RHS today and support our charity
I have forgotten my password
Keep me signed in
Register for free to receive our newsletters, add comments to blogs/articles and to save content.
See what events are on near you and browse your bookmarked pages.
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 1999
the RHS today and get 12 months for the price of 9
Other common names
Siberian flag Siberian iris
Iris may be rhizomatous or bulbous perennials, with narrow leaves and erect stems bearing flowers with 3 large spreading or pendent fall petals, alternating with 3 erect, often smaller, standard petals, in late winter, spring or early summer
I. sibirica is a rhizomatous herbaceous perennial up to 1.2m tall, with narrow grassy foliage and branched stems bearing up to 5 violet-blue flowers 6-7cm wide in early summer, the falls veined purple on white at the base
Europe to C Asia
Toxicity Ingestion may cause severe discomfort
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 or East-facing
Exposure Exposed or Sheltered
MoistureMoist but well-drained
SoilSand, Clay, Chalk, Loam
pHAcid, Alkaline, Neutral
Time to ultimate height
Grow in any good garden soil that is preferably moist but not waterlogged. In drier soils, dig in well-rotted organic matter before planting then apply as a mulch each spring
Propagate by seed or by division of rhizomes from midsummer to early autumn
Suggested planting locations and garden types
Flower borders and beds
City & Courtyard Gardens Coastal Cottage & Informal Garden
Pruning Remove any dying foliage in autumn, old flower stems can be cut down after flowering
Pests May be attacked by slugs, snails and thrips
May be subject to grey moulds
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