Culture (Courtesy Robertson Orchids)
The Cattleya family can be broadly summarized as plants from the Genera Brassavola, Laelia, Cattleya, Sophronitis and combinations of these. They are mostly epiphytic in nature (with the exception of some rock growing Laelia).
Light Requirements: All plants broadly referred to, as Cattleyas need relatively high levels of light to grow and flower well. In frost-free areas, 70% shade through the hot summer months and 50% through the winter seems to produce good results. Cooler climates may find that 50% all year is adequate. Conversely, in extreme heat extra shading will minimize heat stress and sunburn.
Potting Media: Being generally Epiphytic ("Tree Growing") in nature, Cattleyas. For most plants, a medium grade of treated orchid bark is sufficient. Some growers find the addition of 8-10mm size charcoal is beneficial, along with polystyrene balls or coarse perlite. Some growers also use sphagnum moss, however this is not best for the average home grower, with watering and feeding accuracy more critical. Always use treated bark.
Watering: All Cattleyas have pseudobulbs capable of storing moisture during dry periods, so allow plants to just dry slightly between watering. As a very broad guide, once a week in winter and twice a week in summer would be adequate. During very hot dry summer periods 3-4 times a week may be needed and conversely a wet cold winter may mean no watering for 1-2 weeks. A solid roof cover during the winter to give rain and Frost protection will generally give best results. Give the plants a good soaking right through the potting media and over the foliage as well. In very hot summer weather we tend to water late in the afternoons while in winter mid morning is best.
Fertilising: The use of a liquid fertilizer designed for orchids once a week is beneficial during the growing months. Keen growers use a "growth" style fertilizer (Higher Nitrogen, lower Potassium) at the beginning of the growing period (Sept/Oct) and then change to a blossom booster style (Lower Nitrogen, higher Potassium) Jan/Feb to optimize growth and flowering throughout the year. We avoid slow release style Fertilizers
Miniature Cattleya: In general, mini cats have the genus Sophronitis evident somewhere in their breeding background, which explains their improved tolerance to lower temperatures than the larger exhibition or Blc types, and their more compact growth habit. Culturally the above cultural tips still apply but we find they enjoy more moisture and dislike very high temperatures.
Culture (Courtesy Tinonee Orchids)
Pronounced KAT-lee-uh, this group of orchids originates from a large area of tropical and sub-tropical America. They occur in many sizes, shapes and colours but are best known for their large flamboyant bloom. Most grow as epiphytes, or air plants. They have large pseudo bulbs used to store water and have thick, fleshy roots that have the ability to collect moisture from the air.
Light: This is important for good flowering. About 50% is optimal, however if leaves overheat in summer this may need to be increased to 70%. Leaves should be medium green colour and pseudo bulbs rigid and erect without staking. Excessive shading will reduce flowering dramatically.
Temperature: This should range between a minimum of 5-7oC in winter to a maximum of about 30-35oC in summer. I suggest you avoid watering if the temperature falls below 10o. Small plants need to be protected from temperature extremes. High day temperatures, up to 35oC can be tolerated if humidity, air circulation and shading are increased.
Water: This can be provided in two ways, in the pot by watering and in the air by humidity. For a plant growing in good open media, watering twice each week in summer and once every two weeks in winter is sufficient. In summer avoid watering during the heat of the day, in winter only water on a bright sunny morning. The root system on these plants can easily be damage by excess water. If in doubt, defer watering.
Humidity: This is important to Cattleyas, as roots prefer to grow in humid air rather than to be wet. Humidity needs to range from 50% to 80%, about 60% is ideal. In winter watering can be delayed by wetting the greenhouse floor and circulating air around the plants. This technique can also help to cool the plants in summer. If you live in a cool area, it may be necessary to grow your cattleyas under a solid cover so watering can be controlled during winter.
Fertiliser: Fertilize with a balanced NPK (blossom booster) is ideal, apply in the water every second watering.
Pots: These should be shallow, i.e. no deeper than they are wide and should have plenty of holes to allow perfect drainage.
Media: This needs to be coarse and long lasting. Quality treated pine bark is most popular. As a guide use 10mm grade in 100mm pots, 15mm in 150mm pots and 20mm in 200mm pots or larger.
Pests and Diseases: Cattleyas, apart from root rot caused by over watering, can be attacked by pests such as scaly and mealy bug. This is easily controlled by Diazinon or Pest Oil. Slugs and snails love fresh root tips. Hanging plants or growing on mesh benches can help, but snail bait may be necessary.
Disclaimer: The growing guides are provided only as a starting basis to cultivation. Local conditions in your area may require modification to these suggestions. Bankstown Orchid Society Inc. will not be responsible for the results of your cultivation practices.