Chemical Properties
Geranium macrorrhuzum L is the only true geranium and is a sticky, aromatic perennial with hairy, toothed leaves that turn gold in autumn, red to purple fowers and explosive seed dispersal A large number of hybrids have been developed from several Pelargonium species, from which the essential oil is obtained Pelargonium is a perennial plant when growing in subtropi- cal climates; the plant dies in winter and must be planted annually in temperate climates The largest geranium cultivations are on Réunion (island east of Madagascar); more than 50% of the world production of geranium oil comes from this island The cultivated variety is P graveolens Other important geranium cultivations occur in Africa (Algeria, Morocco, Congo, Tanzania, Kenya) and in Europe (Russia, Bulgaria, France, Italy, Spain); South Africa is the only area where geraniums grow wild The various essential oils are distinguished by the geographical name of the country of origin—Réunion geranium, Moroccan geranium, African geranium,etc The parts used are the leaves and stems Geranium has a strong, rose-like odor with a minty undertone and a bitter, rather dis- agreeable favor.
Essential oil composition
The main constituents of the various Pelargonium oils include geraniol, citronellal, ethanol, dimethyl
sulfide, diacetyl, isoamyl alcohol, phallandrene, l-α-pinene, methyl hexyl carbinol, l-isomenthone, α-terpeniol, menthol, linalool,
eugenol and phenethyl alcohol. P. graveolens oil was found to mainly contain linalool, citronellol, cis-caryophyllene and guaiene.
