Pennyroyal is a most useful member of the mint family. Traditionally used to repel fleas, mice and other pests, it is also a main ingredient in herbal insect repellents. And it's so easy to grow!
This upright, creeping perennial reaches 4 to 6 inches tall and spreads indefinitely. Narrow stems are lined with 1½-inch oval leaves and topped with whorls of lilac flowers.
Grow like other mints, in rich, moist soil in sun or partial shade. You can direct-sow the seed or begin it indoors; the seed germinates in about 7 to 21 days, and the seedlings grow rapidly. To avoid it becoming invasive, you might want to plant in containers or in confined areas.
