Mentha species - Mints
Mentha aquatica - Water Mint
Mentha spicata - Spear Mint
Mentha x piperita - Peppermint
Mentha x piperta, is a hybrid of, M. spicata and M. aquatica. From the former it takes the characterstics of sharp leaf teeth and usually glabrous leaves and stems. From aquatica it gets petiolate leaves and a much broader inflorescence, as well as the modification of the scent. This specimen differs from usual piperta in retaining the narrow inflorescence of spicata, but has arguably some genetic input from aquatica in its petiolate leaves. Most hybrids have inserted stamens.
Mentha arvensis - Corn Mint
Mentha arvensis x spicata = M. x gracilis
Mentha spicata x suaveolens = M. x villosa
Mentha aquatica x arvensis = M. x verticillata