Clusters of typically star-shaped flowers appear in spring; O. dubium may start blooming in late winter. Leaves vary from narrow to broad and tend to droop. In areas where they are hardy, ornithogalums can fill many different roles. Set them in open woodlands, wild gardens, or rock gardens, where many kinds will naturalize; plant them in containers or mass them in borders. Where winters are too cold for in-ground growing, plant the bulbs in pots and force them into early bloom indoors or in a greenhouse. Deer and rodents don't eat them.
O. arabicum. STAR OF BETHLEHEM. Zones LS, CS, TS; USDA 8-11. From the eastern Mediterranean. Stems to 2 ft. tall carry clusters of 2-in., waxy-looking white flowers, each centered with a shiny, beadlike black eye. Bluish green, strap-shaped, inch-wide leaves may reach same length as stems, but they're usually floppy. Requires a dry dormant period from midsummer through winter, so best grown in pots. Water from spring through early summer, then let foliage dry out. Store indoors over winter.
O. dubium. Zones LS, CS, TS; USDA 8-11. From South Africa. Stems 812 in. high bear blooms resembling those of O. arabicum, but petals surrounding the beady black eye come in shades of yellow to orange. Dark green to yellowish green, lance-shaped leaves are about 4 in. long, nearly prostrate. Same cultural requirements as O. arabicum.
O. longibracteatum. PREGNANT ONION, FALSE SEA ONION. Zones CS, TS; USDA 9-11. From South Africa. Grown for bulb and foliage rather than its tall wands of small green-and-white flowers. To 3 ft. tall in leaf; flowers increase height to 5 ft. Long, drooping, strap-shaped, light green leaves. Gray-green, smooth-skinned bulb is 34 in. wide and grows on top of, not in, the soil. Bulblets form under skin and grow quite large before they drop out and root. Hardy to 25F. Moderate water.
O. magnum. STAR OF BETHLEHEM. Zones US, MS, LS; USDA 6-8. Native to the Caucasus Mountains, these bulbs are not shy. Growing 12 ft. tall in early summer, it looks like a white camassia. It may reseed modestly, but not enough to become a problem. Tall foliage disappears soon after flowering.
O. nutans. NODDING STAR OF BETHLEHEM. Zones US, MS, LS, CS; USDA 6-9. From the eastern Mediterranean. To 1122 ft. tall. Starlike to nearly bell-shaped, 114-in. flowers are white striped with green on the outside; they have pronounced central clusters of stamens. Up to 15 blooms are spaced along upper part of each stalk. Narrow, floppy, bright green leaves. Spreads rapidly and may become weedy. Sometimes called silver bells.
O. oligophyllum (O. balansae). Zones US, MS, LS; USDA 6-8. From the eastern Mediterranean. Stems grow 35 in. high, bearing thick clusters of white, green-centered, 114-in. blossoms with bright yellow stamens and a faint green stripe on the outside of each petal. Medium green leaves to 6 in. long. This species naturalizes but is not an aggressive spreader.
O. thyrsoides. CHINCHERINCHEE. Zone LS, CS, TS; USDA 8-11. Native to South Africa. Flowering stems grow 1-2 ft. high produce elongated clusters of 2-in., white flowers often with centers tinted green or cream. Upright, bright green leaves grow 1 ft. long, 2 in. wide and usually start to die back while the plants are in bloom. They make excellent cut flowers. Moderate water.
O. umbellatum. STAR OF BETHLEHEM. Zones US, MS, LS, CS; USDA 6-9. Native to the eastern Mediterranean. Erect stems to 1 ft. tall produce clusters of inch-wide, white flowers striped green on the outside. Semierect, grassy-looking leaves are about as long as the flower stems. Cut flowers last well but close at night. Once this species is established, it may naturalize and become weedy.
Plant bulbs in early fall in well-drained soil amended with plenty of organic matter, setting them 3 in. deep and 34 in. apart. Provide regular moisture during growth and bloom. Dig and divide plantings of all species only when plant vigor and bloom quality decline. Indoors, grow in bright light but protect from hottest summer sun. Let soil dry slightly between thorough soakings, and feed every two weeks with a general-purpose liquid houseplant fertilizer. After flowering has ended and leaves begin to yellow, withhold water and fertilizer; don't resume watering and feeding until new growth appears in fall.