The cattleya group is known for large, showy and sometimes fragrant flowers. Some of the most stunning orchids in cultivation are cattleyas, with huge flowers that can measure eight inches across and come in a wide variety of colors and patterns. In the wild, there are several dozen species of cattleya, but it's unlikely you'll find any of these at local garden centers. Because of their ease of growth and sheer beauty, cattleyas are the most hybridized of all orchids, and there are thousands upon thousands of registered hybrids. When shopping for a cattleya, consider an American Orchid Society–awarded clone.
The cattleya orchids like bright light. They can even be acclimated to some direct sunlight, although keep from direct summer sunlight. They will not flower without plenty of light. In the right light conditions, the leaves will be apple green. Darker leaves might indicate too little light, while yellow or brown leaves might indicate too much direct sunlight.
Cattleya are sympodial orchids that grow from an underground rhizome. They typically send up new pseudobulbs in the spring. During the growing season, water heavily, but do not allow them to sit in water. Cut water back when the flowers begin to emerge from their sheaths--water in these sheaths will rot the immature flowers. A well-watered cattleya will have fat lead pseudobulbs.
During the growing season, fertilize with a weak orchid fertilizer weekly (weakly weekly, as the growers say). During the rest period, fertilizer every other week.
Most cattleya produce one new flush of growth annually, and each new pseudobulb should produce flowers that same growing season, often in late summer or winter. Some of the hybrids might produce two blooms annually. When a plant goes into flower, reduce watering to avoid accidentally rotting the flowers. Emerging cattleya flowers are protected by a thin sheath that emerges from the center of the leaf.
Potting and repotting:
Cattleya grow by means of a branching, creeping rhizome with thick, clinging roots. Repotting is stressful, and a plant will usually take a season to recover, so only repot when necessary. They will do well in most orchid mixes, including pink bark, clay pellets, perlite, charcoal, or any well-draining medium. When repotting a cattleya, make sure there is enough room for the rhizome to produce at least two new pseudobulbs before it hits the edge of the pot. Typically, repotting is done in spring, at the beginning of the growing season. Cattleya can also be slab-mounted on tree fern or logs.
Cattleya are not difficult plants, and their flowers are incredibly rewarding. Depending on the species, they may produce just a few showy flowers or bunches of smaller, waxy flowers. Not all cattleya flowers are fragrant, so ask your grower if that's a priority. The biggest mistake most people make with cattleyas is not supplying enough light for the plant to bloom well and/or overwatering. Watch the pseudobulbs—a plump lead pseudobulb indicates a well-hydrated plant.