International Code of Nomenclature for Cultivated Plants

The International Code of Nomenclature for Cultivated Plants (ICNCP) regulates the naming of cultivars, cultivar Groups and  graft-chimaeras. Examples areClematis alpina 'Ruby' : a cultivar within a speciesMagnolia 'Elizabeth' : a hybrid between at least two speciesRhododendron boothii Mishmiense Group: a Group name+Crataegomespilus : a graft-chimaera of Crataegus and Mespilus.Note that the ICNCP does not regulate trademarks for plants: trademarks are regulated by the law of the land involved. Nor does the ICNCP regulate the naming of  plant varieties.
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