How to Grow Cattleya Orchids? A Detailed Explanation of Key Cultivation and Management Knowledge

This article introduces the key cultivation points for Cattleya orchids, including pre-planting preparation, repotting, watering, fertilizing, and staking.

1. Pre-Planting Preparation

To cultivate Cattleya orchids well, you first need a suitable site and excellent environmental conditions. It should not be near industrial or mining areas with air pollution, nor in places with poor ventilation and strong radiant heat surrounded by high-rise buildings. Since Cattleya is an epiphytic orchid, it is not suitable for growing on muddy or concrete ground. It needs a bench or hanging rack to prevent pots from tipping over, as well as an indoor environment where the winter temperature does not drop below 12°C.

Preparation of potting medium: Cattleya orchids have thick pseudobulbs and leaves with vigorous aerial roots, so they generally require a well-draining, loose and breathable growing medium. Commonly used materials include sphagnum moss, fern roots (commonly the roots of the fern Osmunda japonica), bark granules (commonly American redwood bark; in Taiwan, China, longan bark is used; in the mainland, oak bark is used), crushed brick, zeolite, and coconut husk. These potting media must be soaked thoroughly with water before use.

Preparation of planting containers: Cattleya orchids can be grown in two ways: pot culture and hanging basket culture. Pot containers must be water-permeable and breathable. Commonly used types include porous clay pots, plastic pots, glazed-rim ceramic pots, wooden frames, and metal frames. Hanging baskets also require sturdy plastic and wire hooks.

2. Repotting

Repotting is generally done in combination with division propagation. Remove the orchid plant from the pot, clear away the growing medium sticking to the aerial roots, separate the pseudobulbs, expose the root system, and trim broken and rotten roots. If the orchid plant is growing too vigorously, part of the bottom roots can be cut off. Each division should have at least 3 pseudobulbs and carry new shoots. If divided too small, it will affect the recovery growth and flowering of the new plants.

When planting, first fill the bottom of the pot with larger pieces of charcoal or crushed brick to aid drainage, then add a thin layer of growing medium, evenly spread out the Cattleya roots and place them in, then fill growing medium around them and press firmly. Planting too deep is not advisable, as it affects flowering. Note that the new shoots must face toward the edge of the pot, and space should be left for 2 to 3 years of growth.

Newly planted Cattleya orchids should be kept in a semi-shaded, humid place for 2 to 3 weeks, with a small amount of water sprayed on the leaves daily to keep the leaves and pseudobulbs from shrinking. Do not water the roots or fertilize. Once new roots have grown 2 to 3 cm, watering can begin.

3. Watering

Spring and autumn are the growing seasons for Cattleya orchids, requiring ample water and relatively high air humidity. However, watering should wait until the medium in the pot has dried, and should be done in the morning or evening on sunny days. Water slowly so that the medium at the bottom of the pot absorbs water thoroughly. If the pot remains too wet or waterlogged, root diseases will occur.

When not watering regularly, spray a little water on the orchid plant in the morning, also not too much. During the peak growing season in summer, water thoroughly once every 2 to 3 days, and also sprinkle water on the ground and spray the leaves to increase air humidity. Watering in the evening is preferable.

In winter, Cattleya orchids almost stop growing and enter dormancy, but the leaves should still be misted regularly. If the medium in the pot is too dry, choose a sunny morning to water a little, so that the growing medium is moist from top to bottom. Also note that the water temperature must not be too low, otherwise it will damage the orchid plant, causing water-soaked rot patches. When watering in winter, never allow water to remain in the leaf axils or on the leaf surface, as this can easily cause heart rot or leaf rot. After watering, use paper to absorb any accumulated water on the leaf surface and in the leaf axils.

4. Fertilizing

Although the aerial roots of Cattleya orchids can absorb nitrogen from the air and synthesize nitrogen usable by the plant, reasonable fertilizing can make seedlings grow faster, plants more robust, and flowers more vivid. However, improper fertilizing, especially over-fertilizing, is harmful rather than beneficial: in mild cases it causes root damage and rot, and in severe cases it leads to withering and death. Therefore, in the process of cultivating Cattleya orchids, mastering scientific fertilizing methods is very necessary.

5. Staking

In large-scale production, Cattleya orchids are often placed on benches or grown hanging. For bench cultivation, the planting bench should have a bottom groove slightly larger than the base of the orchid pot, so the potted orchid can be placed and fixed securely without easily tipping over. When the orchid leaves grow tall and flower stems emerge, special orchid stakes should be inserted, and overly spreading orchid plants should be tidied into an upright form with ties, but care must be taken not to break the flower stems.

The length of the stake should generally be about equal to the height of the pseudobulbs, which can both prevent the orchid plant from falling over and create a graceful shape. For Cattleya orchids grown hanging, besides hanging the pots firmly in midair, the pots should not be hung too close together, to prevent leaves from colliding and injuring the plants when the wind blows. When the pseudobulbs stand upright, tie them to the stake at the base of the leaves with ties, and bend the tip of the stake close to the sheath leaves for tying the flower stems later.