Wild marjoram is O. vulgare, a perennial common in England in dry copses and on hedge-banks, with many stout stems 1 to 3 ft. high, bearing short-stalked somewhat ovate leaves and clusters of purple flowers. Sweet or knotted marjoram, O. Marjorana, and pot marjoram, O. Onites, are cultivated for the use of their aromatic leaves, either green or dry, for culinary purposes; the tops are cut as the plants begin to flower and are dried slowly in the shade.
Hardy marjoram is a cross of marjoram with oregano that is much more resistant to cold, but is slightly less sweet.
Classification: Marjoram is a member of the mint family, Lamiaceae.