Geranium Oil

''Pelargonium graveolens'' is a ''Pelargonium'' species native to the Cape Provinces and the Northern Provinces of South Africa, Zimbabwe and Mozambique.

Etymology

''Pelargonium'' comes from the Greek πελαργός ''pelargos'' which means stork. Another name for pelargoniums is stork's-bills due to the shape of their fruit. The specific epithet ''graveolens'' refers to the strong-smelling leaves.

Description

''Pelargonium graveolens'' is an erect, multi-branched shrub, that grows up to 1.5 m and has a spread of 1 m. The leaves are deeply incised, velvety and soft to the touch (due to glandular hairs). The flowers vary from pale pink to almost white and the plant flowers from August to January. The leaves may be strongly rose-scented, although the leaf shape and scent vary. Some plants are very strongly scented and others have little or no scent. Some leaves are deeply incised and others less so, being slightly lobed like '' P. capitatum''.

Common names and synonyms

Common names include rose geranium,"Pelargonium graveolens"
''Plants For A Future.'' Accessed June 23, 2007. sweet scented geranium,USDA NCRS
"PLANTS Profile for Pelargonium graveolens (sweet scented geranium)"
''United States Department of Agriculture (USDA), Natural Resources Conservation Service (NCRS), PLANTS Database''. Accessed June 23, 2007. old fashion rose geranium, and rose-scent geranium.

''Pelargonium graveolens'' is also known by taxonomic synonyms ''Geranium terebinthinaceum'' Cav. and ''Pelargonium terebinthinaceum'' (Cav.) Desf. "Rose geranium" is sometimes used to refer to ''Pelargonium incrassatum'' (Andrews) Sims or its synonym ''Pelargonium roseum'' (Andrews) DC. – the herbal name."Pelargonium incrassatum"
''Plants For A Future''. Accessed June 23, 2007. Commercial vendors often list the source of geranium or rose geranium essential oil as ''Pelargonium graveolens'', regardless of its botanical name.

Cultivars and hybrids

Many plants are cultivated under the species name "''Pelargonium graveolens''" but differ from wild specimens as they are of hybrid origin (probably a cross between ''P. graveolens'', '' P. capitatum'' and/or '' P. radens''). There are many cultivars and they have a wide variety of scents, including rose, citrus, mint and cinnamon as well as various fruits. Cultivars and hybrids include:
* ''P.'' 'Graveolens' (or ''Pelargonium graveolens'' hort.) - A rose-scented cultivar; possibly a hybrid between ''P. graveolens'' and ''P. radens'' or ''P. capitatum''. This cultivar is often incorrectly labeled as ''Pelargonium graveolens'' (the species). The main difference between the species and this cultivar is the dissection of the leaf. The species' has about 5 lobes but the cultivar has about 10.
* ''P.'' 'Citrosum' - A lemony, citronella-scented cultivar, similar to ''P.'' 'Graveolens'. It is meant to repel mosquitos and rumour has it that it was made by genetically bonding genes from the citronella grass but this is highly unlikely.
* ''P.'' 'Cinnamon Rose' - A cinnamon-scented cultivar.
* ''P.'' 'Dr Westerlund' - A lemony rose-scented cultivar, similar to ''P.'' 'Graveolens'.
* ''P.'' 'Graveolens Bontrosai' - A genetically challenged form; the leaves are smaller and curl back on themselves and the flowers often do not open fully. Known as ''P.'' 'Colocho' in the US.
* ''P.'' 'Grey Lady Plymouth' Gary Allen - A lemony rose-scented cultivar similar to ''P.'' 'Lady Plymouth'. The leaves are grey–green in colour.
* ''P.'' 'Lady Plymouth' - A minty lemony rose-scented cultivar. A very popular variety with a definite mint scent. Possibly a '' P. radens'' hybrid.
* ''P.'' 'Lara Starshine' - A lemony rose-scented cultivar, similar to ''P.'' 'Graveolens' but with more lemony scented leaves and reddish pink flowers. Bred by Australian plantsman Cliff Blackman.
* ''P.'' 'Lucaeflora' - A rose-scented variety, much more similar to the species that most other cultivars and varieties.
* ''P.'' × ''melissinum'' - The lemon balm pelargonium (lemon balm - ''Melissa officinalis''). This is a hybrid between '' P. crispum'' and ''P. graveolens''.
* ''P.'' 'Mint Rose' - A minty rose-scented cultivar similar to ''P.'' 'Lady Plymouth' but without the variegation of the leaves and lemony undertones.
* ''P.'' 'Secret Love' - An unusual eucalyptus-scented cultivar with pale pink flowers.
* ''P.'' 'Van Leeni' - A lemony rose-scented cultivar, similar to ''P.'' 'Graveolens' and ''P.'' 'Dr Westerlund'.

Others known; ''Camphor Rose'', ''Capri'', ''Granelous'' and ''Little Gem''.

Uses

Both the true species and the cultivated plant may be called rose geranium – pelargoniums are often called geraniums, as they fall within the plant family Geraniaceae, and were previously classified in the same genus. The common ''P.'' 'Graveolens' or ''P.'' 'Rosat' has great importance in the perfume industry. It is cultivated on a large scale and its foliage is distilled for its scent. ''Pelargonium'' distillates and absolutes, commonly known as "geranium oil", are sold for aromatherapy and massage therapy applications. They are also sometimes used to supplement or adulterate more expensive rose oils. As a flavoring, the flowers and leaves are used in cakes, jams, jellies, ice creams, sorbets, salads, sugars, and teas. In addition, it is used as a flavoring agent in some pipe tobaccos, being one of the characteristic "Lakeland scents."

Chemical constituents of geranium oil

A modern analysis listed the presence of over 50 organic compounds in the essential oil of ''P. graveolens'' from an Australian source. Analyses of Indian geranium oils indicated a similar phytochemical profile, and showed that the major constituents (in terms of % composition) were citronellol + nerol and geraniol.R. Gupta, G. R. Mallavarapu, S. Banerjee and S. Kumar (2001). "Characteristics of an isomenthone-rich somaclonal mutant isolated in a geraniol-rich rose-scented geranium accession of Pelargonium graveolens." ''Flavour and Fragrance J.'' 16 319–324.

Gallery

Image:Rose Geranium - cluster.jpg, The flower cluster of cultivated ''P.'' 'Graveolens'
Image:Pelargonium graveolens and bee.jpg, A bee on a flower cluster of cultivated ''P.'' 'Graveolens'
Image:Pelargonium 'Lady Plymouth'.JPG, At Ryton Organic Gardens, near Rugby, Warwickshire.
Image:Geranium1.JPG, ''Pelargonium'' 'Graveolens' leaf
Image:Pelargonium 'Mint Rose'.JPG, An adult ''Pelargonium'' 'Mint Rose' at Ryton Organic Gardens, near Rugby, Warwickshire

References

{{Taxonbar, from=Q164306

graveolens
Medicinal plants
Perfume ingredients
Essential oils
Flora of Mozambique
Flora of Zimbabwe
Flora of the Cape Provinces
Flora of the Northern Provinces
Crops originating from South Africa
Taxa named by Charles Louis L'Héritier de Brutelle