Star of Bethlehem Plant Profile

Extend the spring bulb season with this easy-to-grow plant

Star of Bethlehem plants in bloom

David Beaulieu

Star of Bethlehem is a member of the asparagus family, along with such gardening favorites as Adam's needle (Yucca filamentosa), lily-of-the-valley (Convallaria majalis), and Spanish bluebells (Hyacinthoides hispanica). Star of Bethlehem is not among the earliest bloomers, instead giving you a choice in bulb plants that will flower later in spring. This plant is easy to grow and is even invasive in some areas.

Botanical Name Ornithogalum umbellatum
Common Name Star of Bethlehem, bird's milk, eleven-o'clock lady, nap-at-noon, sleepydick, grass lily
Plant Type Spring-flowering bulb
Mature Size 6 to 12 inches tall and 12 to 24 inches wide
Sun Exposure Full sun to partial shade
Soil Type Moist, rich, and well-drained
Soil pH Slightly acidic to neutral to slightly alkaline
Bloom Time May or June
Flower Color White, with green stripes
Hardiness Zones 5 to 9
Native Area Europe, North Africa, and the Middle East (Mediterranean)

How to Grow Star of Bethlehem

Choose a location with a fertile loam that drains sharply, preferably in full sun. Plant the bulbs of Star of Bethlehem in fall. At planting time, install the bulbs in holes four inches deep and four inches apart. The pointy end of each bulb should be facing up. Fill the holes back in with soil and water. Add a three-inch layer of mulch for wintertime protection if Star of Bethlehem is only borderline-hardy in your area. Remove the mulch when the ground thaws in spring and the plants start to emerge.

The plants will come up the following spring. After flowering is over, you will be left with a mass of tangled, strap-like leaves for a while (its grass-like foliage is never really attractive). Resist the temptation to remove this foliage: As long as it stays green, it is sending nutrients down to its bulbs.

The bulbs will multiply over time, producing what are termed "offsets" or "bulbils." You can dig up these offsets and plant them somewhere else to increase your crop of Star of Bethlehem.

If you choose to leave you Star of Bethlehem alone, it will naturalize and spread on its own, too. It spreads both through its offsets and by seeding. This is one of the reasons why the plant is so easy to grow, but it also accounts for why Star of Bethlehem is often considered a problematic plant: Star of Bethlehem is invasive in some regions.

Because of its potential invasiveness, before you plant Star of Bethlehem, check with your county extension agent to learn if it is invasive in your region. Another drawback with Star of Bethlehem is that it goes dormant by mid-summer, leaving gaps in your planting bed. Different gardeners address these drawbacks in different ways.

To curb the plant's spreading, some deadhead the flowers so that seed is not produced and/or erect barriers as you would to stop the spread of a bamboo. To plug the gaps that its disappearance leaves behind in summer, some plan on having annuals on hand to install, while others prefer to grow perennials next to their Star of Bethlehem that will fill in as summer progresses and hide the spots vacated by Star of Bethlehem.

Light

Although it will grow in partial shade, Star of Bethlehem flowers better in full sun.

Soil

Perhaps the most important requirement in growing Star of Bethlehem is a soil that drains well. This is typical of plants of a Mediterranean origin.

Water

Be sure to give Star of Bethlehem sufficient water when it is young. Once established, it becomes somewhat drought-tolerant.

Fertilizer

Star of Bethlehem flowers best when grown in fertile ground. Fertilize with compost annually.

Other Plants in the Genus

There are other types of Ornithogalum. The various species differ from each other in a number of ways. For example, no other is as hardy as is Ornithogalum umbellatum, one species bears a flower of a color different from the rest, and size also varies from species to species:

  • Ornithogalum arabicum: white flowers, 19 inches tall, zones 9 to 10
  • Ornithogalum dubium: orange flowers, 10 inches tall, zones 7 to 10
  • Ornithogalum nutans: white flowers with a lot of green in them, 16 inches tall, zones 6 to 10
  • Ornithogalum thyrsoides: white flowers, 16 inches tall, zones 7 to 10