A query on Dracaena fragrans at the RHS Horticultural Database returns a number of entries, several of which are listed below: Dracaena fragrans 'Massangeana' Dracaena fragrans (Compacta Group) 'Compacta' Dracaena fragrans (Deremensis Group) 'Lemon Lime' The first is in a format that's typically encountered. The last two include a group designation. Is the group name, including the brackets, considered to be part of the plant's botanical name? Or is it there strictly for reference and is to be omitted in actual usage? I'm guessing the group name is partly due to D. deremensis being reclassified as D. fragrans.
The (Compacta Group) indicates that the cultivar 'Compacta' is one cultivar in a group of similar cultivars; likewise (Deremensis Group) indicates that the cultivar 'Lemon Lime' is one of several similar ones, grouped together by their resemblance to each other.
The grouping helps to identify plants with common characteristics but is it part of a plant's botanical name? I've not encountered this format outside of the RHS database.
Sorry, no, it isn't part of the botanical name - it is a horticultural designation for cultivated plants, not a botanical one.
Format of such names governed by the International Code for Nomenclature of Cultivated Plants, which is in effect an extension of the International Code of Botanical Nomenclature (ICBN). The latter, revised every 5 years, can be consulted at http://www.ibot.sav.sk/karolx/kod/0000Viennatitle.htm, but the former is much harder to find -- you have to buy it at a quite extortionate price!
Are you saying the format used by the RHS is valid, albeit less recognizable? Didn't realize this was a real word - learned something new. Thanks.
Getting serious again, many plant taxonomists (but not all) now choose to reserve botanical nomenclature as governed by the ICBN strictly for wild plants, at least for taxa below the rank of species or primary hybrid. All cultivated derivatives are therefore classified according to the Code for Cultivated Plants. I won't go into details because there is plenty of material available on its principles, but you can find many examples of its consequences in the RHS Plant Finder.
See the article Bos, J.J.; Graven, P.; Hetterscheid, W. L. A. & Van der Wege, J.J. (1992) WILD AND CULTIVATED DRACAENA FRAGRANS. Edinb. Journ. Bot. 49 (3): 311-331, 3 figs, 1 pl. for a thorough review of the species, its many synonyms and cultivars. I have my suspicions that the so-called Compacta group actually represents garden hybrids between D. fragrans and D. braunii (D. sanderiana). The compact growth and reduced inflorescence strongly suggests a hybrid origin with the latter species as one parent.
