Lycaste - THE BEAUTIFUL ONE by Julian Coker
Lycaste is an orchid genus named after the beautiful daughter of King Priam and Queen Hecuba of Troy, and was first named by John Lindley in 1843. It is represented by about fifty species that are found from Mexico to Peru. These are both epiphytic and lithophytic and grow under cool to intermediate glasshouse conditions, depending on the particular species. Lycastes range from being fully deciduous each year to retaining their leaves for 18-20 months, and require a rest period during the winter prior to flowering and recommencement of their growth cycle in spring.
Lycaste plants are characterised by large pseudobulbs that support two to four large ribbed leaves. Flowers arise singly from the base of the pseudobulb and are long lasting, four to eight weeks being common. There is occasionally an autumn flowering from the old pseudobulb but the main flowering occurs in the spring. Generally one flower of excellent quality develops first from the base of the newest pseudobulb and this is followed by the spring flush. From three to five flowers per pseudobulb are usual, especially for hybrids bred from Lycaste skinneri but 30+ flowers over a period are possible from the deciduous species and their hybrids.
The flowers are characterised by having three prominent sepals that open flat and often reflex at their tips. These sepals may have the spatial arrangement of an equilateral triangle or tend more to an inverted T. The petals are lesser segments that typically envelop the column; the labellum is also generally small. Colours are commonly in the yellow-brown-orange range and often there is a marked contrast between the segments. Pinks and whites are represented by Lycaste skinneri and green by Lycaste locusta.
The genus Lycaste is related to Anguloa, Batemannia, Bifrenaria and Xylobium, and hybridises freely with them. Angulocaste and Lycasteria are the most common intergeneric hybrids. Lycaste has been extensively hybridised within itself, Lycaste skinneri being the dominant species used.
Lycastes respond well to good culture, and indeed this is essential for best results. They are best grown in a cool intermediate glasshouse at a minimum temperature of 8-10°C, although cymbidium conditions in a fully enclosed glasshouse during winter are satisfactory. Adequate sunlight, water and feeding during the growing season, coupled with moderate humidity and constant air circulation, will allow for the development of the large pseudobulbs necessary for top flower production.
During winter maintain a relatively high light intensity but decrease the frequency of watering and fertilising. Appropriate watering throughout the year is essential. Copious amounts are required during the growing season together with the application of a balanced fertiliser. At maturation of the pseudobulbs (when the small sheathing bracts turn brown and fall off) decrease the frequency of watering considerably for those species that retain their leaves. Water may be almost completely withheld from the deciduous ones until their flowers or new growths appear.
Mature pseudobulbs may be allowed to approach the stage of wrinkling to create stress and thus initiate flower production. However, do not allow excessive wrinkling to occur. Seedlings should be kept moist at all times. It’s preferable to water directly into the pot, rather than over the leaves or into the new growths. Lycastes are especially sensitive to chlorine, so avoid the use of highly chlorinated tap water.
Lycastes are best grown in black plastic pots that have excellent drainage. The compost must be free draining yet be able to retain adequate moisture and nutrients to supply the plant. A good quality cymbidium compost is ideal. Repotting is done in spring, after the plant has flowered and when the new growths have become established. Repot before the plant outgrows its container, leaving two or three pseudobulbs and the new growth on the leading part of the plant. Lycaste skinneri and hybrids in which this species is dominant are best grown in pots. Backbulb propagations may be attempted but leave at least two pseudobulbs attached to each other. If the plant loses its roots or shows signs of dehydration, transfer it to Sphagnum moss to re-establish a root system before returning it to the growing compost.
Lycastes are subject to the same pests and diseases that trouble other orchid genera. Virus disease, rots and the cosmopolitan pests may all cause trouble and their rapid diagnosis and effective treatment, together with an environment that limits their occurrence, is essential. Of special concern are rots, e.g. Erwinia, that affect the pseudobulbs, and scale, which can occur in heavy infestations all over the plant. Ants often draw attention to the presence of scale.
Lycaste Species .
Lycaste aromatica. Found from Mexico to Guatemala, this species is both epiphytic and lithophytic. It is deciduous and very floriferous, bearing up to 18 flowers per pseudobulb. These appear in spring immediately prior to the appearance of the new growth. The flowers are fragrant, the sepals and petals green-yellow and the labellum and column bright orange-yellow. This species is ideal for specimen culture. It requires cool intermediate conditions for optimal growth.
Lycaste cruenta . Cruenta means stained with blood and refers to the red staining in the centre of the flower and at the base of the labellum. L. cruenta is the most common lycaste in Guatemala. It is epiphytic, deciduous and produces 3-5 flowers from the base of the new pseudobulbs in spring. The sepals are green-yellow, the petals bright yellow-orange and the labellum and column are orange. The inner parts of the segments are spotted red and the base of the labellum sports a bright red splash. This species can be grown successfully in a cool glasshouse.
Lycaste deppei. As with L. aromatica, this species is found from Mexico to Guatemala and is both epiphytic and lithophytic. It is common in cultivation, flowering later than the other species, often during summer. Three to five flowers appear from the base of the pseudobulb in succession prior to the development of the new growth. The flowers have olive-green sepals overlaid with red, white petals, a yellow labellum and a white column. The inner parts of the segments are spotted with red. It grows easily in a cool glasshouse.
Lycaste lasioglossa is a terrestrial species from Guatemala. It produces up to seven flowers from the base of the pseudobulbs in spring. The large flowers have red-brown sepals, yellow petals and a furry yellow labellum. Red spotting occurs on the inner parts of the segments. Cool glasshouse conditions are suitable.
Lycaste locusta is green and indeed locusta is named after the locust. It grows in Peru at the southern end of the Lycaste range. The striking green colour of the flower has attracted the attention of several hybridisers. Two to three flowers are produced from each pseudobulb in spring. It may be grown in a cool glasshouse but is seldom available.
Lycaste macrophylla is one of the most diverse of the species, having many sub-species. Its range extends from Bolivia to Nicaragua, where it grows both as an epiphyte and a lithophyte. The flowers generally have brown to green-brown sepals, white petals and a white labellum. The petals and labellum may have red markings on their inner parts. There is also an albino form with green sepals, white petals and a white labellum. It usually flowers in the spring and grows best in cool intermediate conditions.
Lycaste skinneri is the queen of the lycaste species and is correctly named due to the priority rules of nomenclature. Lycaste virginalis is synonymous but is not the preferred name. It is very variable, both in its habitat and colour forms. Epiphytic in nature, it ranges from Mexico to Guatemala and Honduras; it is the national flower of Guatemala. The flowers are large and attractive, with the sepals varying from white through pink to deep rose and the petals from white to reddish violet. The labellum varies from white to red and is often spotted red. The white column is lined with red spots. There is also a pure white albino form. Three to five flowers are produced from the base of the pseudobulb in spring. They last 4-6 weeks in good condition, even when harvested. This species is best grown in a cool intermediate or cool glasshouse.
Lycaste hybrids . Lycaste skinneri has been by far the most important species used in hybridising, especially for showbench breeding. With the variation in colour from albino white through to deep pink found in its various cultivars, together with its sophisticated form, it has been regularly introduced into lycaste breeding programs. There is an 80% content of this species in the two best known Australian hybrids, Lycaste Koolena (hybridised by Leo Giles) and Lycaste Macama (hybridised by Fred Alcorn). The other two species important in showbench breeding are L. cruenta and L. macrophylla. Other species, namely L. deppei, L. aromatica, L. locusta and L. lasioglossa, have also been used to widen the colour range, to increase the flower count and to extend the flowering time. Famous parents include L. Imschootiana, L. Balliae, L. Sunrise, L. Auburn and L. Koolena. L. Macama is currently the most highly developed showbench grex.
Lycaste is one of the easier orchid genera to grow, although mature plants require considerable space. However, a representative selection of species and hybrids will enhance any collection and certainly add to the pleasure of growing orchids.