Leucojum vernum
Leucojum vernum, called the spring snowflake, is a species of flowering plant in the family Amaryllidaceae. It is native to central and southern Europe from Belgium to Ukraine. It is considered naturalized in north-western Europe, including Great Britain and parts of Scandinavia, and in the US states of Georgia and Florida. This spring flowering bulbous herbaceous perennial is cultivated as an ornamental for a sunny position. The plant multiplies in favourable conditions to form clumps. Each plant bears a single white flower with greenish marks near the tip of the tepal, on a stem about tall, occasionally  more. The Latin specific epithet "vernum" means "relating to Spring". Its close relative, "Leucojum aestivum", flowers in summer. Description. "Leucojum vernum" is tall in flower. Its leaves, which appear at the same time as the flowers and continue to elongate during flowering, are 5–25 mm wide and long, generally reaching to below the level of the flowers. The flowering stem (scape) has a small central cavity and two narrow wings. The pendant flowers appear in spring and are usually solitary, rarely in an umbel of two. The flowers have six white tepals, each with a greenish or yellowish mark just  below the tip. Each tepal is 15–25 mm long. The whitish seeds are about 7 mm long. Taxonomy. "Leucojum vernum" was first described by Carl Linnaeus in 1753. The epithet "vernum" means "of the spring". Varieties. Two varieties are accepted by the World Checklist of Selected Plant Families: A third variety is recognized by some sources, but not by the World Checklist of Selected Plant Families: "Leucojum vernum" var. "carpathicum" is distinguished by the presence of yellow rather than greenish markings at the tip of each tepal. Sources that distinguish var. "vagneri" from var. "vernum" describe it as more vigorous  and flowering earlier, with two flowers per scape. It comes true from seed as it does not cross with var. "vernum". Distribution and habitat. "Leucojum vernum" is native to central Europe and parts of southern and western Europe, including Austria, Belgium, the Czech Republic, Slovakia, Germany, Hungary, Poland, Switzerland, France, Italy, Romania, former Yugoslavia and the Ukraine. It has become naturalized in other parts of Europe, including Great Britain, the Netherlands and parts of Scandinavia, and in Georgia and Florida in the United States. It is found in damp and shady habitats, including woods, up to elevations of 1600 m.  Cultivation. "Leucojum vernum" is cultivated as an ornamental plant for its white flowers in spring. It is described as "easy to grow", either in sun or partial shade, particularly in moist soil and in grass. The species has gained the Royal Horticultural Society's Award of Garden Merit. Cultivars. Many cultivars are available, including: Toxicity. All species of "Leucojum" are poisonous, as the leaves and bulbs contain the toxic alkaloids lycorine and galantamine. Galantamine is used for the treatment of cognitive decline in mild to moderate Alzheimer's disease and various other memory impairments.