Ornithogalum umbellatum (garden star-of-Bethlehem, "Oamana")

Japanese name: オオアマナ （大甘菜）
Scientific name: Ornithogalum umbellatum

[Overview]
A perennial.
It has a spherical bulb about 1.5–2.5 cm long and 1.8–3.2 cm in diameter.
The bulb is poisonous.
6–10 leaves emerge from the base in a rosette; they are linear, about 30 cm long and 0.8 cm wide, with a white line running lengthwise on the upper surface.
The leaves die back after flowering, and the plant is dormant in summer.
An umbel bearing 6–20 flowers is borne at the tip of the flower stalk.
The flowers are white, 2.5 cm across, with 6 tepals that have green stripes on the outer surface.
The flowers open at about 11 a.m. and close at about 3 p.m.
The fruit is a capsule.

[History]
It arrived in Japan in the Meiji period and has become naturalized.

[Cultivation]
Propagate by dividing the bulbs.
It can be left in place for several years.
It prefers sandy soil with good sun, drainage, water retention and aeration.
It dislikes excess moisture.
During leafless dormancy it does better in shade and on the dry side, so in the ground it is best planted under deciduous trees or among summer grasses.
For potted plants, water thoroughly when the soil surface dries during the growing period, and water during dormancy only enough that the soil does not dry out completely.
For plants in the ground, rainfall is sufficient.
Apply compost as base fertilizer; for plants left in the ground, also apply a small amount of compost in winter.
There are no particular pests or diseases, but soft rot may occur if the soil is too wet.

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