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e Hymenocallis 26/11/07 12:19 Page 2 GENUS PROFILE Alberto Grossi Alberto Hymenocallis HEN MY Hymenocallis Caribbean. In 1812, botanist Richard littoralis flowered for the and other A Salisbury named a new genus Wfirst time I was so proud Hymenocallis, noting a few differences that I called a few friends to ask them spider lilies between it and Pancratium: ‘The fruit to visit me. I told them to come in of this genus differs exceedingly from the evening as this is when its scent that of Pancratium, in having only two is greatest. As soon as they saw it seeds in each cell, which swell to a they were astonished by the hand- considerable size, like bulbs, and I some foliage and intoxicating scent. have named it Hymenocallis, from the ‘But they look all alike!’, one told me. beautiful membrane which connects I explained that every species of the filaments.’ He transferred Hymenocallis differs in the length of Pancratium littorale and a few other the tepals, in the shape of the corona, species into the new genus. and in its scent. But he was right; at first glance they are all alike. Characteristics of the genera One could say that they look like Grossi Alberto Hymenocallis is part of the tribe the sea lilies, Pancratium, of the Old Hymenocallis eucharidifolia (top) and Hymenocallideae in the Amaryllidaceae, World, and H. littoralis shares with Hymenocallis littoralis (above) along with the genera Ismene and Pancratium maritimum the same Leptochiton (Meerow et al. 2002). habitat of sandy shorelines. Indeed, ALBERTO GROSSI Some authorities regard the latter Nicolai Josephi Jacquin in Selectarum surveys a group of two genera to be part of Hymenocallis. Stirpium Americanarum Historia (1763) Most species have ‘pancratioid’ floral described this species for the first three related genera; morphology: a large, fragrant, time as P. littorale and he mentioned Hymenocallis, Ismene crateriform flower with a staminal that it thrived on the beaches of the cup, adapted for sphingid moth Isla Tierra Bomba, Colombia, in the and Leptochiton pollination. 222 December 2007 e Hymenocallis 26/11/07 12:19 Page 3 PlantsmanThe Alberto Grossi Alberto Grossi Alberto Hymenocallis speciosa, one of the tropical, evergreen species Hymenocallis caribaea, plants under this name are often H. ‘Tropical Giant’ The three genera have bulbs that tube bearing six elongated segments Speciosa alliance are roundish or oblong, covered in a that are usually white, occasionally Only a handful of species belong to tunic, and producing thick whitish yellow or greenish. The basal part of this alliance, they are tropical in origin roots. The bulb is up to 15cm across the stamens is fused to form the with evergreen, petiolate, broad leaves. in larger species of Hymenocallis but corona or staminal cup that is funnel- Hymenocallis speciosa and H. tubiflora smaller in Ismene and Leptochiton. shaped or rotate. The stamens are are the most widely grown. The leaves Most produce offsets but a few species more or less straight but in Ismene are about 60cm long; in H. speciosa are rhizomatous. Ismene and they are incurved. The seeds are large, the blade is lanceolate, in H. tubiflora Leptochiton are deciduous, but oblong and green. the petiole is very long and the blade Hymenocallis from tropical habitats A lot of species are fragrant, mainly is almost cordate. They flower in are evergreen whereas those from in the evening or night to attract autumn or winter with me and need arid areas are deciduous. The leaves sphingid moths. The scent is sweet, high temperatures (at least 15°C at vary in number and length and are like that of Mirabilis jalapa, or spicy. night) and moisture all year long. usually distichously arranged but Each flower lasts one or two days. The compost has to be rich with H. eucharidifolia has a rosette arrange- good drainage and they are best ment. They range from 5-7mm Hymenocallis grown in shade. They offset freely. wide, sessile, linear and glaucous in Hymenocallis contains about 70 species, H. graminifolia to 15cm wide, distributed across the southeastern Caribaea alliance petioled, lanceolate and bright green United States, Mexico, Central The members of this alliance are in H. speciosa. In Ismene the leaf base America, the West Indies and north- tropical and subtropical species with forms a pseudostem up to 50cm tall. ern South America. Mexico is home evergreen, sessile, broad, oblong The flowers, one or more, are held to the greatest number of species leaves. Hymenocallis caribaea is the on long stems emerging from the with a secondary area of diversity in most widely grown of this group, it inner leaves. The stems are usually the US. Only three species are ende- flowers in summer and offsets freely. compressed, 2-edged and solid. They mic to South America (H. littoralis, It is best grown in full or half sun, may be produced at the beginning of H. pedalis and H. tubiflora). The and kept moist when growing but a the growing season, along with the species have been grouped into six little drier in winter when a temp- leaves, or later. The flowers have a alliances based on morphological erature above 15°C is required. greenish, funnel- or salver-shaped characters by Traub (1962). What is commonly sold or ➤ December 2007 223 e Hymenocallis 26/11/07 12:19 Page 4 GENUS PROFILE Alberto Grossi Alberto Andrea Jones Andrea Ismene longipetala, a species that passes on its curling tepals to hybrid progeny Hymenocallis ‘Tropical Giant’, an old, sterile cultivar often grown in botanical gardens as in mid summer. It needs a very wet stem bears two, rarely three, flowers H. caribaea is H. ‘Tropical Giant’, an sandy compost and warmth all year with pale green tepals and a white old cultivar of possible hybrid origin. round to grow well. corona. Hymenocallis palmeri is similar This cultivar has glossy, sword-shaped, Hymenocallis acutifolia is similar but but has one single-flowered scape. arching leaves and in midsummer is more tolerant of dry periods as it is each stout stem bears 12 or more found on river banks that are dry for Mexicana alliance highly scented flowers. Hymenocallis part of the year. Hymenocallis riparia Species in this alliance are native to caribaea is smaller in all its parts and is deciduous. Mexico. They are deciduous with has more erect, rigid leaves, also, the broadly elliptic or elliptic-lorate leaves. tepals are held in one plane whereas Caroliniana alliance They can cope with a very dry rest those of ‘Tropical Giant’ are more The species of this alliance are dist- period and begin to grow and flower obviously borne in two planes. The ributed throughout the southeastern with the late spring rains. cultivar does not normally set seed United States, usually in seasonally The commonest in cultivation is but I sometimes get a few set when I inundated habitats. They are H. harrisiana which has a flower stem cross it with other Hymenocallis species. deciduous and the leaves are linear, of about 25–30cm normally bearing The luxurious foliage and vigour of linear-lorate or ensiform and shortly four flowers. It is hardy to USDA ‘Tropical Giant’ makes it one of my narrowed to the obtuse apex. Zone 7 if kept dry during the rest favourites in the tropical landscape. Flowering in spring and summer, period. Distinguished by its rosette- Hymenocallis latifolia is another none are common in cultivation but like leaf arrangement, H. eucharidi- favourite, often grown in the sandy those most likely to be encountered folia, first introduced in 1884, has beach gardens of the Gulf of Mexico. are H. caroliniana, H. coronaria, been reintroduced in the last decade. It is a large plant with erect, strap- H. galvestonensis and H. rotata. They shaped leaves and the small cupped need warm, wet conditions during Leptochiton flowers are vanilla-scented and open the growing season with a little This genus has only two species, at the beginning of the summer. moisture when dormant. L. helianthus and L. quitoensis, and is native to southwest Ecuador and Littoralis alliance Henryae alliance northwest Peru at low elevations. It Hymenocallis littoralis has evergreen, Hymenocallis henryae is known from shares with Hymenocallis the absence linear, leathery leaves and it flowers scattered localities in Florida. Each of a pseudostem but it differs in 224 December 2007 e Hymenocallis 26/11/07 12:19 Page 5 PlantsmanThe having black rather than green seeds. rewatered after the medium has exceeds the long leaves which are 90 The flowers are yellow in L. helianthus completely dried up. In autumn, x 3–5cm. The flowers are semi- and white in L. quitoensis. Both are after the leaves have yellowed and transparent, white, with a long rare in cultivation. shrivelled, they need to experience funnelform perianth, greenish at the an absolutely dry winter. base. The narrow curly tepals are Ismene When grown in a container, three about 10cm long and the corona is This genus is characterised by the bulbs in a 20cm pot is ideal. If lifted about 3cm in diameter. This species presence of a pseudostem, consisting from a border before winter you has been involved in a lot of hybrids. of leaf bases forming a sheathing should avoid damaging the large Ismene x festalis (I. calathina x I. longi- neck. From this emerges a flattened roots and store them in sand in a petala) was first created by the stalk bearing several flowers. All cool place. English bulb fancier Arthington species are deciduous and the genus Another interesting hybrid, but Worsley. Ismene ‘Advance’ is a hybrid has been split into three subgenera. rare in cultivation, is Hymenocallis x between I.