Leucojum are like the bigger brother of snowdrops, still with dainty white nodding flowers but taller and more robust looking. Unlike snowdrops the petals are all the same size and have a more waxen texture, while a distinctive feature is the yellow or green spot at the tip of each petal. There are early-spring, late-spring and autumn flowering species.
There are around 10 species across Western Europe, the Middle East and North Africa, but there are only two species commonly grown in UK gardens. L. vernum Award of Garden Merit (AGM) is the first to flower, usually between February and March, hence known as the spring snowflake. It is around 20cm high and does well in moist soil and shade, reflecting its natural habitat. Coming in around three times as high is L. aestivum, confusingly referred to as the summer snowflake but usually flowering in late spring, between April and May. They form nice clumps for the herbaceous or mixed border.
Another variety, L. autumnale, flowers in September, is shorter than L. vernum AGM and needs quite different conditions — full sun and sandy soil. It suits being planted in a warm, sunny spot at the front of a border, in a rock garden or along the edge of a path.
There are a few other smaller, delicate species that hail from drier habitats. These include L. nicaeense, L. trichophyllum and L. roseum. There is debate over whether these smaller species with narrow leaves and unmarked flowers should be returned to the genus Acis, but for the purpose of fullness I am including them here. They need well-drained conditions, protection from winter wet and a hot, dry dormant period in summer, so are best grown in the alpine house or a bulb frame, but they can be tried in a hot and sunny position outside.
The bulbs of the two most commonly grown species, L. vernum AGM and L. aestivum, should be planted in autumn, about 10cm deep and 8-10cm apart. Because both species come from moist or wet habitats, they naturalise well in damp grass. L. aestivum in particular thrives in moist, rich soil and alongside water sources. Like all bulbs the leaves should be left to die back completely before being removed. To increase stock, collect seed, sow in containers and place in a cold frame in autumn or remove offsets once the leaves have died down. Pests to watch out for are slugs and narcissus bulb fly.
What the specialists say
Neil McCulloch, proprietor, Bulbs Galore, Manchester
"Both L. vernum and L. aestivum are robust, hardy bulbs that can increase well once established. L. aestivum ‘Gravetye Giant’ is an excellent variety that is taller and more vigorous. It was found in William Robinson’s garden, Gravetye Manor in West Sussex.
"Another nice form is L. vernum var. carpathicum, which has the yellow tips on the petals instead of the green.
"I’m not really an expert on the smaller species — sometimes classified as Acis — such as autumnale, roseum and trichophyllum, but I love the look of autumnale with its slender reddy/brown scapes and nodding flowers on slender pedicels. L. roseum show off that lovely pale-pink striping too. If grown in pots their delicate beauty can be appreciated more than in the garden, where they may not thrive."
Stephen Graham, planteria manager, Woodlands Garden Centre, London
"We generally sell the Leucojum bulbs in autumn, between September and November. We tell customers that they do best in a moist soil, even by ponds, and like full or part shade.
"Customers are sometimes confused with snowdrops but we explain that the snowflakes are quite a lot taller and more robust. They have a delicate fragrance that has been likened to violets, so that’s a good selling point, as are the nice markings on the petals of L. vernum and L. aestivum."
Species and varieties
? L. aestivum, or the summer snowflake, produces glossy, deep-green strappy leaves and leafless stems bearing green-tipped, white, bell-shaped flowers in late spring. Height: 50cm.
? L. aestivum ‘Gravetye Giant’ AGM (H7) is a robust, vigorous form of the summer snowflake that is taller than the type. It also produces glossy, deep-green strappy leaves and leafless stems bearing slightly fragrant, white, bell-shaped flowers, each segment tipped with green. Height: 90cm.
? L. aestivum var. pulchellum is smaller than the type and flowers approximately two weeks earlier. Height: 20cm.
? L. autumnale, the autumn snowflake, produces slender green to red/brown stems topped with nodding white flowers flushed pink at the base, from late summer to autumn. Pale-green leaves follow the flowers. Increases well by offsets. Height: 16cm.
? L. nicaeense has narrow, deep-green to glaucous leaves that can curl and start to emerge in autumn, and one-to-three flowers on short pedicels with a slender style, coming later in the spring. Height: 15cm.
? L. roseum has narrow, deep-green leaves that come with or after the flowers. The flowers, produced between summer and autumn, are white with a lovely pale-pink stripe down the median line of each petal. Height: 15cm.
? L. trichophyllum produces slender scapes topped with two-to-four flowers on slender pedicels. The flowers, which come during winter to spring, are white or flushed pink to purple. Height: 25cm.
? L. vernum AGM (H5), the spring snowflake, has glossy, dark-green, strappy leaves and erect stems with broadly bell-shaped, green-tipped white flowers. Flowering time is February to March. Height: 20cm.
? L. vernum var. carpathicum is a form of the spring snowflake with yellow tips to the floral segments. It is less inclined to build into large clumps but spreads by seeding when happy. It comes true from seed and strong bulbs often bear two flowers on each scape.
? L. vernum var. vagneri is a vigorous variety that is twin- or three-flowered with green tips. The petals are narrower than the type, giving a spidery appearance. It increases well and comes true from seed. Height: 25cm.
Thank you to Floramedia, which supplied the images for this article from its photo library