Stellaria irrigua, commonly known as umbrella starwort or umbellate starwort, is a perennial herb that is native to moist meadows, streambanks, and wetland margins in western North America, as well as parts of Asia, including Siberia. It typically forms slender, prostrate stems that can reach up to 8 inches in length. The plant is characterized by its small, oval, opposite leaves and its distinctive umbel-shaped inflorescences, which bear tiny greenish-white flowers with five petals that are deeply cleft, giving the appearance of ten petals. The flowering season extends from late spring to early summer, and while the flowers are not particularly showy, they do add a delicate texture to the plant’s overall appearance.

Umbrella starwort is valued for its ability to thrive in moist, cool environments and is often used in native plant gardens, rain gardens, and as a ground cover in wetland restoration projects. It prefers consistently moist soil and can tolerate partial shade, although it will also grow in full sun if sufficient moisture is present. This plant is relatively low-maintenance, but gardeners should ensure that the soil does not dry out. It is not known for serious pest or disease problems, but it can be sensitive to drought conditions.CC BY-SA 4.0