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Unlike most other groups of plants orchids hybridise widely in nature. For the last 150 years they have been widely crossed in cultivation to produce over 110,000 hybrids (called grexes). Orchid hybrids can involve up to 20 distinct species from up to nine distinct natural genera. The first hybrid was made in 1854 and detailed records have been maintained since that time.

For the last 50 years this has been done by the International Registration Authority for Orchid Hybrids, since 1962 under the aegis of The Royal Horticultural Society. Over 3,000 new orchid hybrids are being added annually. A bi-monthly update is published with The Orchid Review, the orchid journal of the RHS, and reprinted in several orchid journals around the world. The update is also available online in pdf format.

View the orchid hybrid lists


How to register an orchid hybrid

Please fill out and submit the application form below. Basic information required is the name to be registered, the names of both parent plants and the name of the originator. A brief description and or colour image is also useful.

The registration fee from 1 January 2010 is £10.00 (US$ 16.50) subject to annual review.

Please remit the fee with your application preferably by credit card.
Dollar cheques. The bank charge for a dollar cheque is larger than a registration fee. Therefore dollar cheques can not be accepted for single applications. Please use a credit card or send a single dollar cheque for several applications.

In case of queries, please e-mail the orchid registrar at

The postal address for applications is:
83 Victoria Road, Selston, Nottinghamshire, NG16 6AR, UK.
Tel. +44 1773 511814, Fax. +44 115 876 7963

Guidelines and rules for composing grex, group and cultivar names

The names of cultivated plants are governed by the International Code of Nomenclature for Cultivated Plants (ICNCP). A summary of the main points is included below to assist those who need to create new names for registration or publication. Note that the ICNCP now supersedes the Handbook on Orchid Nomenclature and Registration 4th ed. of 1993.

Download a summary of the guidelines and rules (pdf)

Hybrid genera

The generic names used for orchid hybrids must comply with the International Code of Botanical Nomenclature (ICBN).

Application forms

Search the register

The International Orchid Register can be searched online by two methods…

Parentage Search

This method can be used to identify any grexes from particular seed and pollen parents.

Grex Name Search

This method can be used to find the parentage of particular grexes.

Search the International Orchid Register online *

* It should be noted that all dates of registration prior to 1990 are given to the year only (e.g. 1/1/65)

The Advisory Sub-Committee on Orchid Hybrid Registration (AsCOHR)

The purpose of this sub-committee is to advise the RHS in matters relating to orchid nomenclature and taxonomy and their application to the International Register of Orchid Hybrids (Sander’s List).

View the 2012 issue (416kb pdf)

View the 2011 issue (365kB pdf)

View the 2010 issue (344kB pdf)


The RHS publishes the Supplement of New Orchid Hybrids (Sander's List) quarterly, and lists since 2001 are available to download for free.

View the orchid hybrid lists

The RHS once published The Handbook on Orchid Nomenclature and Registration, now out of print, which has been superseded by The International Code of Nomenclature for Cultivated Plants, 8th edition, 2009.

It also publishes regular addenda which include all hybrid generic names registered for a certain period and includes parentage, names of registrant and originator and year of registration.

View the orchid publications here

Further information

Significant developments in the history of orchid hybrids and their registration (pdf)

Checking other orchid names

Botanical names of genera, species and some lower ranks may be checked using the databases at:

The International Plant Names Index - lists all known botanical names for higher plants

Kew World Monocots Checklist - lists currently accepted names with their synonyms. The orchid register usually follows the names accepted therein

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The Orchid Review

The Orchid Review is the oldest and most influential orchid magazine in the world and essential reading for anyone with a passion for orchids.

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Plant bulletins

The results of many of our major trials are now being produced in full colour bulletins. These bulletins include full descriptions of the Award of Garden Merit plants, botanical background and cultivation information.

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