Sweet Flag (Acorus calamus)
The foliage of this unusual herb is similar to that of an iris. This perennial's natural habitat is shallow water and it's best grown in a pond, pool, or other damp setting.
Sweet flag is propagated by rhizome division. This is best done in the spring and fall. Rhizomes should be lifted in the second or third year. If left longer they may become hollow. Harvest the leaves and hang to dry in the fall. The fragrance intensifies during the drying process.
The rhizome is used to alleviate stomach acidity.
Leaves can be used as a substitute for vanilla pods. Try leaving a few leaves in a jar of sugar for a few days for vanilla-flavored sugar. They can also be cut up and stored in dry foods to prevent infestation by weevils. Leaves and rhizomes are a nice addition to potpourri.