Lysimachia quadrifolia, commonly known as Whorled Loosestrife, is a perennial herb native to moist meadows, prairies, and open woodlands of the eastern United States and Canada. It typically grows to a height of up to 2 feet tall and is characterized by its whorled leaves and erect form. The plant produces distinctive yellow flowers with reddish centers that bloom from June to August, which are moderately showy and attract pollinators. The flowers are borne in the leaf axils and at the tips of the branching stems.

Whorled Loosestrife is valued for its bright yellow flowers and its ability to thrive in moist to wet conditions, making it suitable for rain gardens, wetland plantings, and naturalized areas. It is also used in border plantings for its vertical accent and summer blooms. This species prefers full sun to part shade and requires moist to wet, calcareous soils with good drainage. While generally low-maintenance, it can spread aggressively in favorable conditions and may need to be managed to prevent unwanted naturalization.CC BY-SA 4.0