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All ratings refer to the UK growing conditions unless otherwise stated. Minimum
temperature ranges (in degrees C) are shown in brackets
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.
'Devon Skies' is an evergreen perennial, to 20cm tall, producing tufts of upright, grass-like foliage and clusters of starry, sky-blue flowers, with a dark throat and yellow eye, all summer
'Aunt May' is an evergreen perennial forming a clump of erect, sword-shaped grey-green leaves margined with cream, with erect leafy stems bearing several clusters of pale yellow flowers in summer
O. douglasii produces slender, upright stems sheathed with grass-like leaves. The flowers are 2cm long, nodding, bell-shaped and a rich purple with a satiny texture. They appear in early spring
'California Skies' is a perennial to 20cm producing tufts of upright, grass-like foliage and clusters of starry, clear sky-blue flowers with a dark throat and yellow eye all summer
S. striatum is a clump-forming perennial, to 80cm tall, with fans of grey-green, narrow, linear to lance-shaped leaves. In summer, stiff, upright stems carry clusters of pale yellow, star-shaped flowers along their length
Last-listed in the RHS Plant Finder in 2016
This plant is listed in the RHS Plant Finder book. At present our information about this plant is limited to a list of the nurseries that supply it. In time we will be adding more details including a description, growing information, advice and photographs.
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Britain’s best gardening annual, available now from RHS Mail Order and all good bookshops.
Listed in the RHS Plant Finder
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