ORCHIDS GREEN HOUSES -SHADE STRUCTURES
CULTIVATION OF HYBRIDS AND PLANTS
ORCHIDS ASIA provides a range of accessories , green management systems and assist in making of green houses and shade houses intended for cultivation of the horticulture crops.
Orchids, Anthuriums, Heliconias, Pineapple, Foliage
Orchid House include green houses, shade houses and slat houses.
We offer technology support, hardware and systems for construction of orchid houses from few 100 sqm to many acres of green houses.
Included are the plain shade houses, arched houses, and professional quality gable type green houses for phalenopsis and cymbidium culitivation.
Within the business of potted plants for growing we work with orchids, anthuriums, and foliage groups. We provide different growing system for each family and accordingly these are discussed here. Most of orchids for pot plants include Dendrobiums, Vandas and Phalenopsis family.
There are also orchids which can be grown in open sun. Various terete leaves species of Vanda, Aranda , Arachnis, Renanthera etc. can be grown in open trenches filled with bark pieces, charcoal as is done in Ceylon, Singapore, and Thailand.
Indirect sunlight is ideal for orchids. Seedlings requires less than adult plants. Very poor light tends to produce weak plants and retards flowering. A plant which has been grown in shade should be gradually be shifted to sunlight.
Pots / Container:
Orchids should be potted in small container/spots according to the size of the plants. As a thumb rule, orchids should be under potted to get more flowers. Any kind of pot/container which can hold medium and provide aeration is suitable. Most of the people prefer ceramic pots which retain moisture longer than plastic pots. Vandaceous and Sarcaenthene orchids can be grown in teak-wood baskets.
Orchid plants should not be disturbed frequently and repotting done only when absolutely necessary. Orchids like Cymbidium, react favourably when repotted after 2-3 years whereas Vandeceous orchids and Paphiopedilum should not be disturbed unless very necessary.
Terrestrial orchids, like Spathoglottis, Phaius and Calanthe, should be grown in 20-25 cm pots with 1:1:1 mixture of leaf mould, FYM and wood mix. For Paphiopedilum A mixture of 2 parts leaf mould, 2 parts wood mix and 1 part each of charcoal is recommended.
Chunks of hard-wood charcoal alone as potting substance were superior then eleven other potting media. Tree fern fibre also performed better than the other media while coconut husk and over-burnt brick as planting substance had adverse effects on growth and flowering of orchid plants. Some latest media tried for growing orchids are gravel jelly, fir bark, tree fern fibre and polyurethene foam.
Orchids like Aerides, Arachnis, Epidendrum, Renanthera, Phalaenopsis, Vanda and Dendrobium can be propagated by cutting. Orchids cutting are usually more bigger and should possesses one or more roots. Cutting are usually potted in propagation beds or directly in pots after treating the cut ends with fungicides to prevent rotting.
Cutting of genera, like Aerides, Arachnis, Vanda etc., are very hardy and can be directly potted in pots, whereas those of dendrobium and Phalaenopsis need special care to root and should be potted in propagation beds.
GROWING PLANTS UNDER CONTROL CONDITIONS
The orchids are marketed both as potted plants and as cut-flowers. In the past few years, the orchid trade has increased both in volume and value throughout the world. Presently, Thailand and Taiwan are the largest producers of orchids for pot-plants under greenhouses; the orchids are grown in an area of about 600 ha .Over 300 million orchids were exported from the country.
Many developing countries including Malaysia, Thailand, Singapore, Taiwan , Phillipines, Sri Lanka, and Indonesia have established their own orchid Industries. A large export market is available if the products are right and marketed properly.
Several structural elements are used in preparing a shade house or green house including use of Bamboo, Wood, Steel pipes, concrete and other available building materials. Normally a green house might have a cover made of UV protected clear PE or PP films with single or double glazing and shade cloths made out of different percentage to filter light. Based on the type of variety grown the requirement for light and other conditions will vary.
Orchids in nature grow protected from the tropical sun by the shades of trees. Under controlled condition the orchids can be grown in specially designed orchidaria or orchid houses, running North and South and made from materials like split bamboo, glass, fibre glass, etc. A central tank filled with water helps in increasing humidity .
However, it must be clear that all types of orchids cannot be grown under one roof. While tropical orchid enjoy humid, warm atmosphere and burst into activity during rainy season, temperate orchid should be growing in cool houses. Orchids dislike sudden change in temperature, however a difference of 10oC - 20oC between day and night temperature is beneficial. The best suitable range is 18 C to 30 C, proper ventilation is must to provide fresh air and also helps in reducing the temperature.
Humidity / Watering:
Humid warm atmosphere is most essential for the growth of most of the tropical orchids, which do not have well established root system. It is a good idea to have a water tank or pool in the center of the orchidaria to maintain humidity, which should not be less than 30% at night and 80% during day time, The plants should be watered 2-3 times a day and should not be allowed to dry up during hot climate. Plants in active growth require more water. Similarly plants in baskets require more water than those in pots. Care should be taken to water the plants with a fine spray by using standard nozzles and not to hit the plants with powerful jets of water.
In nature, orchids obtain their supply of inorganic nutrients like calcium, magnesium, iron, potassium, nitrogen and traces of manganese, boron, copper, zinc etc. from the tree on which they are growing and also from atmosphere and decaying vegetables and dropping of birds. However under controlled conditions they have to be supplied with all these major and minor nutrients.
Taking into consideration the special need of different orchids, a large number of fertilizer mixtures, both solid and liquid, are available in market. Liquid fertilizers are much more quickly absorbed and can be applied more frequently. As the orchids are slow growing, slow release fertilizers like osmocote can be used to get very good result. Usage of fertilizers should also depend on stage of growth. During vegetative growth, large quantities of nitrogen are required while during flowering, nitrogen should be reduced and amount of phosphate increased.