• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases


Cornus alba 'Siberica'The National Plant Collection of Cornus is grown at RHS Garden Rosemoor, the Society's Devon garden. A wide range of representatives both of flowering and coloured-stem dogwoods are established in appropriate areas throughout the garden.

Some early disease fears have been overcome and the collection is being actively expanded, with more than 30 species and more than 40 cultivars represented. Fortunately, there has been no sign of Cornus anthracnose disease.

Some of the collection has been catalogued in the RHS Horticultural Database, and a start has been made on the preparation of herbarium specimens from the collection.

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The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.