The International Rhododendron Register and Checklist Second Edition was published in two volumes in 2004. It has not been revised or reprinted. Instead, omissions, corrections and additions have been published annually as Supplements. They are available for download here or on the RHS website
IMPORTANT: The 2004 Register should be read in conjunction with its later Supplements and if certain data is of particular importance, checks should be made that further updates have not been made to an entry. Should uncorrected errors be noticed, unrecorded information be known which might be relevant or of interest, or queries arise from entries, it is important to contact the International Rhododendron Registrar, who is keen to ensure the Register is as complete and accurate as possible.
The International Rhododendron Registrar, The Royal Horticultural Society's Garden, Wisley, Woking, Surrey, GU23 6QB, UK.
We are grateful to the Royal Horticultural Society for granting the Group permission to offer this publication digitally whilst an online service to the International Rhododendron Register database is developed.
The Register is offered here in two volumes exactly as the printed edition and also as a single volume although please take note that the files are large! It has been scanned and converted into searchable text using OCR technology. It is NOT perfect but it is hoped that it is sufficiently accurate to allow meaningful research.
Until now the Register has only been available to those who purchased the printed edition. Thanks to the generosity of the RHS, it is now made freely available to all for information and research.
The Register is a detailed directory of registered hybrids and selections of rhododendrons (including azaleas, azaleodendrons and vireyas) representing the careful assembly of records compiled over more than a century and a half. The system of notation used to standardise entries has inevitably led to the use of abbreviations and the presentation of each entry in a precise order which needs explanation for the first time user. For the reader's convenience, A Companion Guide to Using the Register has been produced which can be printed out or opened on-screen to refer to alongside the main files.