Ornithogalum umbellatum aka Star Of Bethlehem

Ornithogalum umbellatum is a perennial bulb called star of Bethlehem. It belongs to the asparagus family, Asparagaceae. Sources place its home in Europe and the Mediterranean region. Kew gives central Europe as its native range. It now grows beyond its home range in North America. Introduced plants also grow in the Baltic states and southern Australia. It grows fast and forms upright clumps from underground bulbs.

Garden plants stand about 0.5–1 foot (0.15–0.30 m) tall. Clumps spread about 1–2 feet (0.30–0.61 m) wide. RHS gives a broader height range, reaching 1.6 feet (0.5 m). Its spread estimate is smaller, at 0.33 feet (0.1 m). Slim green leaves rise from a rosette at ground level. Each leaf often has a white line down its middle. The smooth leaves arch up, then bend down near the middle. They droop and fade as the flowers start to open.

Straight stems carry loose flower clusters in May and June. Each stem holds ten to twenty white, star-shaped flowers. Six tepals form each bloom, with green stripes outside. Flowers open around midday, then shut at dusk or in clouds. The blooms have a scent and draw bees. After flowering, capsules form with three chambers holding black seeds. The plant then rests, with its leaves dying back.

Grow it in rich soil that drains well. It prefers full sun but also grows in part shade. Give it moisture while it grows and flowers. Established bulbs cope with dry soil and summer drought. Heavy rain late in summer can harm dormant bulbs. Sources list USDA zones 4–9 and UK hardiness H6. It suits meadows, woodland edges, and less formal borders. It also provides ground cover and flowers for cutting. Bulb offsets and seeds can spread it beyond planted beds. Dense colonies can crowd out other plants in spring. Alabama lists it as a noxious weed. Avoid sites where its spread would harm nearby plants.

Serious pests and diseases are uncommon, but wet soil can rot bulbs. Contact with bulbs may cause a rash in sensitive people. The plant is poisonous to people, pets, and grazing animals. Its toxins occur throughout the plant, with most in the bulb. Eating it can cause stomach upset; large amounts can disrupt heart rhythm. Some accounts describe bulbs and flowers as food, but also warn of poison risks.