Hymenocallis festalis Blanche

The Ismene or Hymenocallis festalis, beautifully called the Peruvian daffodil or spider lily, is a tender bulb of Andean origin, cultivated for its dazzling and fragrant flowering that lasts for two months. Its curious and magnificent flowers, composed of a trumpet-shaped crown extended by long, curved petals, resemble large white spiders. They are carried in umbels by a stem emerging from a tuft of ribbon-like foliage similar to that of Amaryllis. Delightfully fragrant and sculptural, these flowers last a long time in a vase and make spectacular and refined bouquets, of great class. Install it near the house, in large pots on the terrace, or even in open ground in our coastal regions spared from frost.

Ismene, formerly known as Hymenocallis, belongs to the Amaryllidaceae family, just like snowdrops, Nerines, and Lycoris. Ismene x festalis is a horticultural hybrid plant resulting from the crossbreeding between I. narcissiflora and I. longipetala. The former is native to the Peruvian Andes, the latter from the southwest of Ecuador to the northwest of Peru. Ismenes are not very hardy and appreciate a mild climate where frosts are rare and brief, and they adapt well to pot cultivation.

In bloom, Ismene x festalis reaches a height of 50-60cm (20-24in) with a spread of 30-40cm (12-16in). Its growing season extends from spring to autumn, and its dormant period corresponds to winter. The basal foliage forms a spreading clump composed of large ribbon-like leaves of a shiny tender green. From late spring to the end of summer depending on the climate, for two months, cylindrical flower stems measuring 60cm (24in) emerge from the foliage. Each carries at its tip an umbel of 6 flowers reaching 10-15cm (4-6in) in diameter, white, washed with green at the centre, with a sweet fragrance. Each flower, slightly inclined towards the ground, is curiously architectural: it consists of a wide trumpet, called a staminal crown, which stretches into six long, slightly undulating and downward-curving petals.

Ismene x festalis is an exotic, sculptural plant, pleasantly fragrant, which is well suited for ornamenting terraces or the surroundings of the house. It will thrive in a soil close to neutrality, well-drained and rich in organic matter, conditions that can easily be provided in a pot that will be stored during winter. A bit difficult to match due to its strong personality, it can however be surrounded by foliage such as ferns, green or purple fennel, and light flowers such as Gaura and Aster cordifolius. A delicate flowering grass like Stipa pennata could also accompany it. Our coastal regions spared from frost can welcome it in open ground, in partial shade, with Heucheras, Lycoris, and hostas for example.