There are approximately 60 species from tropical America. They are mainly epiphytic and occur naturally in a wide variety of habitats. Some can grow on rocks (ie. lithophytes).
Cane like pseudobulbs arise from creeping rhizomes, and each pseudobulb has between one and three (rarely four) very stiff, thick leaves.
The flowers are borne on racemes emerging from a terminal flower stem. A flower stem may carry several flowers or only one.
These variable and often very brightly coloured flower are frequently large, with petals that are broader than the sepals, sepals that are similar to each other and a three lobed lip.
Cattleyas are one of the most popular orchids grown in warm climates or in greenhouses in cooler areas. Cattleyas do best at temperatures between 13 and 30 degrees celsius, at least 50% humidity, with indirect light and plenty of air movement.
Most Cattleyas like as much indirect sun as possible in cool climates, but will require shading in warmer climates or over a hot summer. If foliage is pale, increased shading may be needed. In too much shade, foliage can become lush and dark green. Such foliage is more susceptible to disease and less likely to flower. A medium, light green foliage is best on a Cattleya.
If you want flowers soon, buy plants with at least 5 to 8 pseudobulbs on them. Smaller plants can take years to flower.
When the plant is overgrown in the pot, the rhizome attached to the pseudobulb can be partly cut and left till new growth begins on it or completely severed and the pseudobulb planted separately to the rest of the plant immediately. Each new plant should have 3 or more pseudobulbs.
Unlike some orchids, Cattleyas generally do not have a dormant period when they should be left drier. The roots need to be moist but never over wet, all year round. On hot days they are best watered early morning, and allowed to dry out through the day. Large established plants often only need watering once each week. With high humidity, warm temperatures and good ventilation,the likelihood of disease problems is greatly reduced. A small fan can be used 24 hours a day to keep air moving around the plants. Reduce watering in winter, but do not allow the stems to shrivel or shrink through dryness.
Thousands of hybrid Cattleyas have been bred by crossing one species of Cattleya with another or with other closely related groups of orchids. Resulting plants often have spectacular flowers 15cm or more across in colours ranging from browns and reds to yellows, purples and whites.
Orchid growers commonly use abbreviations to designate Cattleya hybrids (see chapter one), as the names can become quite lengthy and complicated. Most hybrids with Cattleya in the parentage have similar growing requirements to pure Cattleyas.
Species fall into two groups. The following comments are generally true for each group.
Single leaved Forms have only 1 leaf arising from the pseudobulb. Pseudobulbs are a medium size, swollen and well spaced. Flowers are particularly large, but rarely more than 4 flowers, opening in succession over two or three weeks.
Multiple leaved forms normally have two, or sometimes three leaves (rarely four). These have thinner pseudobulbs which can be very short or very long, according to species, and the number of flowers on a spike can be many (with some species, up to 20)
C. Aclandiae is an epiphyte. It has pseudobulbs tha vary from 1 cm (0.4 inches) to 1 metre (3.3 feet) long, with two leaved pseudobulbs. The petals and sepals are a greenish yellow with dark spots and the short lip is pale rose. C. Aclandiae Nigrescens is similar but with very dark brown petals & sepals.
C. aurantiaca (syn. Epidendrum aurantiaca) is naturally epiphytic. It produces the smallest cattleya flowers, to only 4 cm (1.6 inches) across. The flower colour is variable; commonly rich shades of orange to red. Pseudobulbs are 2 leaved and the plant can reach 30 cm (12 inches) tall.
C. Bowringiana is a 2 leaved type which is terrestrial in the wild growing on rock or sand. Flowers are variable but often in shades of rich pink with darker lip and throat markings. There are several named cultivars grown, each one different.
C. labiata (Autumn Cattleya) is an epiphyte from Brazil. It flowers autumn to early Spring, and has only one leaf to each pseudobulb. C. labiata has flowers to 15 cm (6 inches) across, which have variable characteristics. Flower colour is commonly pale rose to purplish petals and sepals with colour variation in the lip. There are a number of well known cultivars which are sometimes included within this species, and considered by other authorities as separate species (including: C. labiata Mendelii and C. labiata Mossiae, C. labiata Percivaliana).
C. Leopoldii (syn. C. guttata var. Leopoldii) can have two or three leaves to a pseudobulb. Flowers are to 10 cm (4 inches) across, brown to green with reddish purple dots and a predominantly white lip. In the past it was considered a variety of C. guttata, but is now recognised as a separate species by many authorities.
C. luteola has one leaf per pseudobulb, yellow flowers sometimes striped, and to approximately 5 cm (2 inches) across. The lip pale to white and wavy margin. C. luteola is a relatively small Cattleya, rarely more than 15 cm (6 inches) tall, which is sometimes used to breed dwarf hybrids. It is best grown as an epiphyte mounted on a slab.
C. maxima occur naturally both as epiphytes high in trees, and as lithophytes on limestone outcrops. The pseudobulbs grow to 30 cm (12 inches) long containing one leaf. There are three to fifteen flowers on a raceme, to 12 cm (4.8 inches) across, predominantly pale lilac to rose, with a light red to purplish lip marked with dark veins and orange-yellow patch. Types originating from higher altitudes differ to those from lowland sites.
C. Mossiae is a large plant with pseudobulbs to 40 cm (16 inches) or longer and leaves to 20 cm (8 inches) long. There are usually three or four large flowers (to 18 cm or 7.2 inches across) to a flower stem. There are many different varieties,with flowers varying from rich pink or lilac to white. The inside of the lip usually has darker markings.
C. warscewiczii has one leaf per pseudobulb. It produces some of the largest flowers of all Cattleyas, to 20 cm (8 inches) across. There are several varieties, which were more commonly cultivated in the past than today. The blooms commonly have a pleasant strong scent, with pale purple petals and sepals with dark purplish lip bearing lighter markings.
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