Lemongrass is pretty well known to lovers of oriental cuisine (which seems to be nearly everybody in the UK). But just as you can get varieties of mint that smell of lemons – there are also kinds of lemongrass that don’t have the distinctive aroma of lemongrass.
Palmarosa oil bucks the trend by having a smell that is more reminiscent of roses or geraniums than lemon. But from a botanist’s point of view, it is definitely a lemongrass. Its scientific name is Cymbopogon martinii, whereas the more common lemongrass used as a fragrance in cosmetics (by me at least) is Cymbopogon flexuosus.
One of the features of this particular oil I find appealing is the way the oil is made. It is distilled in the fields where it is grown. The grass, once the oil has been extracted, is dried out. It can then be used as fuel for the next batch to be distilled. It is both sustainable and carbon neutral.
The distinctive smell of palmarosa comes from its very high content of geraniol. This is found in other plants as well. It is a large component of lemongrass, rose and of course geraniums. Disappointingly for those with tidy minds, it has quite a low level in geranium despite the name. But palmarosa is totally dominated by geraniol, it constitutes over 80% of the oil.
Geraniol is a member of terpene family, a bunch of interesting and charismatic compounds that get up to all sorts of capers. It came as no surprise to learn that geraniol has a shady past. There is a big similarity between the smell of geraniol rich rose oil and even more geraniol rich palmarosa. Given the big price difference, it was inevitable that a trade would arise between India where the grass was grown and Persia which at one time in the Middle Ages led the world in oil production technology. Palmarosa was the ideal additive to make your rose oil go a bit further and increase your profit margins.
Palmarosa also has a track record of use in India’s long tradition of Ayuvedic medicine. It was used as a skin protecting and cleansing agent. Ayuvedic practices are a bit more sophisticated than simple folk remedies. It often turns out that scientific scrutiny backs up the uses of plant materials that have been worked out over the years by practitioners.
It looks like palmarosa may fall into that category. About ten years ago a paper was published showing that palmarosa had an antibacterial activity. This has been confirmed more recently by another group. Though as I say it doesn’t really surprise me. There are no doubt plenty of uses we can find for these kinds of materials just waiting to be discovered.
Antimicrobial action of palmarosa oil (Cymbopogon martinii) on Saccharomyces cerevisia