THE SECTIONS OF PELARGONIUM
Wayne Handlos, Ph.D.
As people have studied the plants in the genus Pelargonium, they have become aware of groups of species that share similar characteristics. These may be similarities in leaf characteristics, floral similarities, similar chromosome number, etc. Over the years, some botanists have thought that these groups merited more formal recognition. Sometimes these groupings have been given their own generic name, but more often in the geranium family these groups have been recognized as subgroups within the genus Pelargonium. These groups are now most commonly called "sections".
Sections provide a convenient way of looking at the species within a genus. They are not essential to understanding the group but they do serve to separate species which are similar in some or many ways. The most recent treatment of Pelargonium recognizes 16 sections. Most of these sections contain species that are fairly commonly cultivated by Pelargonium fanciers or those who are enamored of the species.
In alphabetical order the sections with representative species are:
Campylia - P. ovale, P. tricolor
Chorisma - P. mollicomum, P. tetragonum
Ciconium - P. peltatum, P. zonale
Cortusina - P. cortusifolium, P. echinatum, P. xerophyton
Glaucophyllum - P. grandiflorum, P. laevigatum, P. lanceolatum
Hoarea - P. oblongatum, P. parvipetalum
Isopetalum - P. cotyledonis
Jenkinsonia - P. trifidum
Ligularia - P. crassipes, P. fulgidum, P. hirtum
Myrrhidium - P. caucalifolium, P. suburbanum
Otidia - P. alternans, P. carnosum, P. crithmifolium, P. laxum
Pelargonium - P. capitatum, P. citronellum, P. cordifolium, P. crispum, P. cucullatum, P.
denticulatum, P. glutinosum, P. graveolens, P. panduriforme, P. papilionaceum, P. radens, P. tomentosum
Peristera - P. australe, P. drummondii, P. grossularioides
Polyactium - P. bowkeri, P. gibbosum, P. lobatum, P. triste
Reniformia - P. abrotanifolium, P. exstipulatum, P. ionidiflorum, P. odoratissimum, P. reniforme, P. sidoides
Subsucculentia - P. grandicalcaratum, P. otaviense, P. spinosum
If you want further information, consult Diana Miller�s book Pelargoniums, page 15, for a synopsis and description of the sections or visit the website called The Pelargonium Page (http://www2.arnes.si/~mstrli/pp.html) for a detailed description of each section, plus information on chromosome numbers, DNA evidence, etc. and a list of all of the species included in each section.