• 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

The RHS is part of a worldwide network of International Cultivar Registration Authorities (ICRAs), which play a vital role in promoting uniformity, accuracy and stability in the naming of cultivated plants. It is a non-statutory, voluntary process that benefits the whole horticultural community. ICRAs are appointed by the International Society for Horticultural Science through its Commission for Nomenclature and Registration.

Most important horticultural genera are covered by an ICRA and a full list of these can be found as Appendix I of the International Code of Nomenclature for Cultivated Plants - 2009. Listings are available online.

The RHS is ICRA for nine major groups, currently processing well over 4,000 names a year in the plant groups listed below:

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