Pilea pumila

Pilea pumila, commonly known as clearweed, Canadian clearweed, coolwort or richweed, is an herbaceous plant in the nettle family (Urticaceae). It is native to Asia and eastern North America, where it is broadly distributed. This plant is most often found in rich loamy soil, usually in moist to wet areas. Its natural habitat is in forests or other lightly shaded conditions. It is a common plant throughout its range, and forms large colonies where it is found. It grows in both high-quality habitats and in ecologically degraded areas. Due to its high tolerance for disturbance, it is often seen near buildings and as a garden weed....read more on Wikipedia.