Mentha pulegium
A low, spreading perennial mint that creeps along the ground at 4 to 12 inches tall, rooting at the nodes to form a dense, fast-knitting mat. It grows in full sun to partial shade and favors moist to wet soils, tolerating poorly drained sites and seasonal dampness where other ground covers struggle. The small oval leaves are strongly aromatic, and in summer it bears tiered whorls of lilac to lavender flowers along upright stems that draw pollinators. Use it as an aromatic lawn substitute in damp ground, along pond and swale margins, between pavers in moist areas, and for erosion control on low, wet slopes.