Originally published on Herbal Medicine from Your Garden
Today’s herb is the European pennyroyal, Mentha pulegium, and specifically not the American pennyroyal, Hedeoma pulegioides, which is not closely related.
Pennyroyal is a protected species, and is becoming difficult to find in the wild, though it does grow in abundance in the New Forest and on the shores of Lough Beg in Northern Ireland, according to the UK Biodiversity Action Plan. Its natural habitat is short turf on clay or silt, which is trampled by animals or other traffic and wet for part of the year. It may be an ideal candidate for a driveway!
Both European and American pennyroyal contain similar active ingredients, although in the American variety, ketones are also found. Do not eat either European or American pennyroyal, as they are toxic and may be lethal, and in particular do not consume the essential oil or use it on the skin, even diluted, although it can be used externally, in an oil burner for example.
This herb is not suitable for internal use by pregnant women, and to be honest, there are safer and easier to grow/obtain candidates for all of the uses for which it has traditionally been recommended. For this reason, I’m not even going to mention these, but suggest you use one of the other mints, which do not have the same level of toxicity.
Protected species may not be picked or harvested from the wild, but should you have an abundance of pennyroyal growing in your garden, you can use the petals in pot pourri. You would need an awful lot of plants to get a worthwhile quantity, though.
If you would like information on how to grow organic pennyroyal, visit the Gardenzone.