Answer: There's a great deal of confusion over oregano, and sometimes marjoram is sold as oregano, which further confuses the issue. I think you have both in your garden. Origanum Majorana (sweet marjoram) is a tender perennial with square stems covered with small hairs. The flowers have knotlike shapes before blossoming and the white or pink flowers are clustered on spikes. Origanum vulgare are also perennials with square, hairy stems, but the flowers are tubular, two-lipped, rose-purple to white, with four protruding stamens, growing one short spikes. The full flavored oregano is the one with the purple flowers. Hope this clarifies things for you!
A good source for an even more detailed description of these plants is Rodale's Illustrated Encyclopedia of Herbs (ISBN# 0-87857-699).
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