Cattleya orchids are wonderful plants with attractive flowers, available in many shapes, colors and sizes. Though perhaps less-popular today than in the past, they have been kept by horticulturalists for over a century. Caring for Cattleya orchids is not difficult, though they do typically enjoy a brighter environment than certain other orchids. In northern Europe, care for Cattleya orchids indoors is perhaps not as easy as for Phalaenopsis for example, at least in terms of encouraging flowering, but they do make excellent houseplants.
Like Dendrobium, Cymbidium and Oncidium, Cattleya is a sympodial orchid: that is to say it grows from a rhizome, producing pseudobulbs in the direction of growth. New pseudobulbs appear each season with either one leaf (unifoliate) or two (bifoliate). Flower spikes or sheaths appear from the new pseudobulbs.
The Cattleya genus is part of the Orchidaceae family. It contains 42 known species, and over the last 100 years, many of them have been hybridized, both with other Cattleya species, and orchids of other genera entirely. Many available Cattleya hybrids have flowers that can measure 15cm across; the largest flowers can even exceed 20cm. Magenta pink, or 'orchid' color flowers are fairly typical, but all other colors are available; except for genuine blue and black. A Cattleya hybrid in a local store will typically be quite hardy, and an easy plant to care for.
Wild Cattleya orchids come from much of South America, upwards into Central America. They inhabit a diverse range of forest habitats: coastal swamps, tropical rainforest, and hill and mountain forests with elevations of up to 2000m. Many species come from Brazil, but they grow in all South American countries upwards of Argentina, then through Panama and as far as Costa Rica. Cattleya orchid care is easiest when you understand the preferred environment of your plant. In the case of hybrids, watching the plants reaction to the conditions in which you are keeping it is essential.
Wild Cattleya orchids typically grow in jungles and forests, usually as epiphytes on forks in branches. They also grow on moist rocks, clinging on tightly with their roots. They survive in a range of conditions, from the lowland heat and moisture of dense Amazon rainforest, to higher altitude positions in mountain ranges of Central and South America. Epiphytes and lithophytes have no access to ground water, and must absorb all moisture from rain that lands on their roots or from humidity in the air. Understanding this is critical when considering your Cattleya houseplant care regime. Treating them in a similar manor to other non-epiphyte houseplants is likely to kill your orchid. Roots must always be well ventilated!
Because Cattleya orchids are epiphytes, a well-draining potting medium is a critical part of their care. Coarse or medium coarse fir bark is a good choice. It will retain some small amount of moisture, but also offers good root ventilation. If the potting medium does not drain sufficiently, the Cattleya orchid will certainly not thrive, and may also be susceptible mould infestations. Orchid mixes including fir bark, carbon and perlite are also great choices.
The Cattleya orchid hails from the tropics and requires warm temperatures. There is some variation in altitude though; lowland species require more warmth than upland and mountain dwellers. Plants from higher elevations can make better houseplants in cooler climates. A healthy and well established Cattleya orchid can usually cope with occasional temperature extremes, but such instances should be avoided. Prolonged exposure to extreme temperatures is highly detrimental to the plant. If you want to provide your plant with ideal Cattleya orchid care, you keep it in an environment where the summertime day temperature stays between and 75 and 85°F (24 and 29°C). The recommended night temperature is 60-65°F (15.5-18°C). Hybrids may well have slightly different requirements, depending on the parent plants.
Although rainforest epiphytes often require somewhat shaded conditions, Cattleya live higher up trees where light penetration through the canopy is somewhat greater. Good Cattleya care involves providing your orchid with brighter light conditions than some other orchids. They should however be shaded, perhaps with a net curtain, from the most intense mid-day sun; between 11 am and 3 pm. Correct lighting can be monitored by looking at the orchid's leaves. If the leaves start to yellow, your Cattleya orchid is probably exposed to too intense sun-light. By contrast, leaves that become dark green, suggest a plant that needs more sun.
As described above, Cattleya orchids are epiphytes and in the wild grow on tree branches and similar. They are therefore ill adapted to a life where they are forced to grow in a soggy medium. Letting the potting medium dry out thoroughly before you water the orchid is recommended. Push your finger down into the plants media. If there is still moisture in the pot, your Cattleya does not yet need watering. Shrivelled or wrinkled pseudobulbs are a sure sign the orchid needs watering. Plants can have water poured through their pots, or, in dry conditions, the pots can be placed for a few minutes in a shallow container of water. In either case, once removed, the orchid must be allowed to drain fully. Watering should always be performed in the morning, giving your orchid the whole day to dry out.
Many people water orchids with tap water, and this can be fine, as long as it has been aged, firstly to let chlorine dissipate, but also to warm up slightly. Room temperature water is best, because it is possible to shock your orchid with excessively cold water. Distilled water and rainwater are also used by many orchid keepers. It is important to understand the differences between these water sources, as they can impact on your orchid care regime. see what water for orchids.
Keeping Cattleya orchids on a humidity tray is an excellent way of providing moisture. It is no substitute for watering, though offers a more natural environment, and reduces the possibility of your orchid becoming too dry.
A high-nitrogen fertilizer (25-9-9) can be used 12 months a year. 1 teaspoon per month is usually enough. It can be a good idea to split up the servings over several days instead of giving your orchid one massive feeding.
Cattleya orchid care involves repotting your Cattleya orchid when it has outgrown its pot. This will usually happen every 2-3 year. Do not repot more frequently, unless the potting medium show clear signs of deteriorating. A potting medium that turns sour or becomes infested with mould should be exchanged at once. The same is true for a medium that does no longer drain well.
Cattleya flowers vary in size, with some varieties have very large flowers indeed. Wild type orchids often have bright pink blooms, but there is considerable variation, especially when the huge numbers of hybrids are considered. Unfortunately, Cattleya blooms are not as long lasting as Phalaenopsis for example, though they are certainly their equal in appearance.
Flower buds usually appear in sheaths: leaf-like structures that grow from between the leaf and pseudobulb. The buds, and ultimately flowers can take quite some time to emerge from the sheath. When the last flower has fallen from your Cattleya orchid, it is a good idea to cut the flower spike all the way down the stem. If you want to help the plant sealing the wound, you can apply melted candle wax or some cinnamon powder.
A small selection of notable Cattleya species: