Sunday, March 05, 2006

Growing Dendrobiums


Growing Dendrobiums
Written by [Philippine Orchid Review] Rolita V. Spowart
Sunday, 01 February 1998
Dendrobiums are one of the largest and the most diverse genera in the orchid family. This diversity in structure and habitat of the different species results in dissimilar cultural requirements between types. For this article, the discussion of the cultural requirements of Dendrobiums will be limited to the hybrids commonly grown in the Philippines. This category will include modern , intersectional hybrids mainly between the sections Phalaenanthe and not Spathulata. Occasionally, progenitors of these hybrids will include species from the section Latouria.

Dendrobiums are a delight to grow for hobbyists because of their affordable price, relative ease of culture and their diversity of form and color.




Potting and Mounting.

Proper potting or mounting is a vita aspect of Dendrobium growing as this will affect the development of the root system. A clean and robust root system should be single most important objective of a Dendrobium grower. With a healthy root system comes a dedrobium that can uptake water and nutrients readily and resist pest and diseases more easily.

The most commonly used potting media for commercially-grown Dendrobiums are charcoal,. Coconut husk and three fern fiber. While coco husk is an excellent medium, it disintegrates rapidly thereby requiring frequent repotting.

Charcoal and tree-fern fiber are more durable media for the non-commercial orchid grower. Dendrobiums mounted on kakawate twigs or driftwoods also perform exceptionally well under the conditions of the local backyard growers.




Light and Shade.

Dendrobiums grow very well under relatively high light. A shade of 30% (double fishnet) is adequate for growers who need artificial shade. Younger Dendrobiums will require more shade (50%). For growers who cannot stand to have netting installed in their gardens, Dendrobiums should be positioned in an are that gets full sun from dawn till about 11:00 o’clock am and shade or filtered light thereafter.

Heavier shade will result in Dendrobiums with lusher, dark green foliage on taller plants while higher light intensity will result in more blooms. It is wise to provide more shade to Dendrobiums at heir younger stage while they are foliage. As soon as they are ready to bloom, provide higher light intensity to ensure early flowering.




Watering.

The frequency of watering is dictated by growing conditions. Conditions of higher light intensity and stronger air current require heavier, more frequent watering. The growing media is also a factor to consider in adequate watering. Coco husk retains moisture longer while charcoal dries out quicker. Dendrobiums mounted on driftwoods will require daily watering as the roots are continually air-dried without the benefit of a water-retaining medium.

Many experts advise Dendrobiums to be watered enough so that the pseudobulbs do not shrivel. Any more than this will promote root and leaf diseases. Providing less water to the point of shriveling will result in leaf loss.

Dendrobiums favor their roots to be constantly moist while their foliage to be dry. Dendrobiums will adjust slowly to the level of watering that they are given. Give them too little and they will develop more roots and thinner, smaller leaves. However, it is important to note that drastic changes in moisture level will result in leaf loss and bud drop. Changes brought about by climate conditions should be aided gradually.




Fertilization

Dendrobiums are fast growing orchids that require heavy feeding. Commercial growers are known to fertilize their Dendrobiums at one and a half times the recommended rate at 3 times the recommended frequency. This will work so long as the other requirements and conditions are ideal.

Hobbyists will varying growing conditions will be on the safe side if they apply a balanced fertilizer at the manufacturer’s recommended rate. A higher nitrogen fertilizer will be required for younger plants.

A one to two-time-a-week washing or heavy watering in between fertilizer application will ensure that salt build-up in the plant and the growing media is prevented.




Important Considerations

While Dendrobiums are fast-growing plants if they are grown under ideal conditions, they are also one of the most temperamental of orchids. As a great majority of the species progenitor are deciduous in nature, these modern hybrids respond similarly to sudden changes in growing conditions. Drastic changes in temperature, moisture or light level and the slightest injury to its roots almost always result in bud or leaf drop.




Commercially Important Cultivar Groups




UH Varieties

The cut-flower varieties of the University of Hawaii is a commercially important group of cultivars as they are ideally suited for cut-flower production. While these groups does not exhibit the more spectacular form and color of other newer hybrids, their performance in floriferousness and vigor is extraordinary.




Purple Phalaenopsis Types

D. Udomsri is the typical example of this group. The large , round flowers of deep velvet dark purple colors remain popular only in the cut-flower trade but also for the potted-plant market. Larger, darker flowers of thicker substance on more vigorous plants have been the prevalent improvement in he newer hybrids of this type.




Yellows and Greens

Mainly descended from the species D. schulleri, these modern Dendrobiums have excelled in their color and from in the past decade. D. Tongchai Gold from Thailand and D. Palolo Sunshine from Hawaii are some yellow hybrids of significance. D. Bangkok Green, D. Burana Fancy and D. Burana Jade of Bangkok are commercially significant greens.




Blues

The bluer color is a sought-after shade in the Dendrobium pot-plant market. Important progenitors of the blue Dendrobiums are D. taurinum and the blue form of D. gouldii. A true sky-blue colored Dendrobium remains to be many a breeder’s dream.




Horn and Semi-Horn Types

Malaysian breeders have long created hybrids of these types from D. taurinum, D. lasianthera, D. helix, and D. strebloceras. Hawaiian breeders of old have made use of D. gouldii, D. stratiotes and D. cannaliculatum for their horn type breeding.




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2 Comments:

At 4:16 AM, Blogger Mary Ann Libao said...

What is the name of the orchid in the picture and its scientific name? Thank you.

 
At 4:16 AM, Blogger Mary Ann Libao said...

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