Cattleya

Cattleya  Like most other cultivated orchids, cattleyas are epiphytes, or air-plants. Because they are epiphytic, they have developed water-storage organs, called pseudobulbs, and have large, fleshy roots covered with a spongy, water-retentive velamen.

Light & Air  Bright light to some sun must be given to the plants, but no direct sun in the middle of the day. This means an east, shaded- south (as with a sheer curtain) or west window in the home. Leaves should be a medium green color. Humidity can be provided in the home by placing the plants on trays of gravel, partially filled with water so that the plants stand above the water. Misting the plants in the morning only is helpful in dry climates. Air should always be moving around the plants to prevent fungal or bacterial disease, especially if high humidity and/or cool temperatures exist.

Temperatures  Recommended temperatures are 55°F to 60°F at night and 70°F to 85°F during the day. A 10° to 20° differential between day and night is recommended, especially for mature plants. Higher day temperatures can be tolerated (up to 95° F), if humid, air circulation and shading are increased.

Water & Fertilizing  Water should be provided in two ways: in the pot by watering and in the air as humidity. Watering in the pot is dictated by many criteria - size and type of pot, temperature, light, etc. Mature cattleyas need to dry out thoroughly before being watered again. Seedlings need slightly more constant moisture. Compare the weight of a dry pot of the same size and type of medium; it can indicate if a plant needs water. A freshly sharpened pencil inserted in the potting medium can be an indicator of moisture. If in doubt, it's best to wait a day or two until watering. Plants in active growth need more water than plants that are resting. Water below 50 degrees F may injure plants, as will softened water. Fertilizer must be given to cattleyas on a regular schedule. High-phosphorus or bloom booster (10-30-20) formulation may be used occasionally (every 4 to 6 applications) to make sturdy growths and promote healthy blooming. When in active growth, plants need fertilizer every two weeks, and when not growing, once a month. Fertilizer can also be applied with every watering at 1/4 recommended dilution. Thorough flushing with clear water every month is recommended to prevent buildup of fertilizer salts.

Potting  They are accustomed to being dry at the roots between waterings, and therefore should be potted in a very porous, free-draining medium.