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CYMBIDIUM HABITATS
GROWTH CYCLES

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Most of the hybrid cymbidium plants commonly grown incorporate species that naturally grow either as terrestrials - they grow at the base of trees and on the ground in the quite considerable depth of forest litter - or as epiphytes - they grow on the trees themselves. Collectors who have brought cymbidiums back from their native environment have found them growing under a great many different conditions. Some were clinging to trees as epiphytes, others were found in the soil where decaying leaves kept their roots cool and protected from drying out during the periods of little rainfall. But usually the finest specimens were found on or near fallen trees where their roots could penetrate rotting wood.


There are two main growth patterns of cymbidiums. In the one type flower spikes are produced from the immature pseudobulbs. Here the new growth commences in the late winter or in early spring, this growth not being completely mature when in late summer to early autumn the flower spike is produced, the pseudobulb continuing to grow as the spike develops. The second type commences growth during the summer, at around the-same time as the flower spikes are produced from the parent pseudobulb. These have minimal growth during the late autumn and winter, bursting into rapid growth in the spring, producing mature pseudobulbs by mid-summer which are capable of making new growths and producing flower spikes. Whatever sequence of growth is followed, it is important that maximum growth be achieved, as it will only be the strong growths that will be capable of producing the best flowers. It is important that the pseudobulbs reach the level of maturity necessary for them to produce flower spikes as relevant to their growth pattern if that stage of growth is not reached, there is no way the plant can flower.

Research studies have noted that for good growth and flower production, an abundance of light is necessary. The exposure of plants in their natural environment varies with the particular situation, but almost invariably the plants with the most light produce far more flowers and better growths.Giving abundant light under glasshouse contidions is, however, complicated by the accompanying increase in house temperatures. Most plants can continue growth up to 27 C, but above this plant metabolism will be upset, and total growth reduced with the plant destroyed if very high temperatures are maintained for any appreciable period of time. It is noted that light is more often than not THE limiting factor of growth, therefore growing the plants where full light can be given without the undesirable tempera-ture problems should be sought. This will generally be achieved by placing the plants outside, and not in a closed glasshouse, during the summer months. This is also confirmed by the ecological studies of Lack of enough light at low enough temperatures and high enough humidity and air flow is usually the limiting factor" . . . for successful culture.

Those flowers you so enjoy are initiated during the summer period, from mid summer  through to mid autumn. For the results we so desire, the plant's particular requirements must be met.

Most of the present day hybrids incorporate a relatively few species in their breed-ing, and most of these species originate from the same area, the foothills of the Himalayas, although some extend through Burma to Asia. The TYPICAL CYMBIDIUM HABITAT as subjected to heavy rains, from 1320 to 3540 mm (52 to 100 inches) per annum, mostly during the June to October (De-cember to April Southern Hemisphere) wet season, which corresponds to the vegetative growth period of these plants. Since the humidity is also high, rarely below 50 per cent, the plants grow under very damp conditions, especially at night when temperatures fall and precipitation occurs. The day temperatures vary from 21 to 38 oC the night temperatures range from 5 to 10 oC, but often reach 10 to 15 oC.

It will also be noted that the summer rainfall is very high, with about 70 per cent of the annual rain falling during ttis period. In contrast, the winters (November, December, January-May, June and July Southern Hemisphere equivalent) are very dry, with only 25 mm (1.0%) of the total annual rainfall of 2376 mm falling during these months. The information confirms that the autumn and winters are fairly bright, although dry, with the summers wet with many overcast rainy days.

Details of the Himalayan habitat are shown in the habitat pages on this site. You are strongly recommended to study this materia, together with that for the habitat the warmer growing Asiatic cymbiium species, which originate from the tropical lowland forest habitat, also subjected to the summer monsoon influence.

The habitat information must be food for thought; are you providing conditions that are anything like this? I think that it will be obvious that during the summer, an enclosed growing area will not be suitable, and that most plants would be more at home outside during this period, where temperatures will be lower, and where they can receive plenty of fresh moving air.

abundant light under glasshouse conditions is, however, complicated by the accom-panying increase in tissue temperatures as well as higher air temperatures. It is therefore important that a balance be achieved between the level of light and glass- The plants obviously enjoy plenty of water during the summer, and the POTTING MIX must be able to accommodate this. It must also, however, be able to dry out during the winter to prevent root damage, especially if the plants are grown in an area that is subjected to cold weather. The watering habits of the owner will also influence the mix composition, as will local environmental conditions. What will be suitable for one grower in one area may not be suitable elsewhere for someone else; hence it is recommended that you see what other growers are doing in your area, and who are growing under similar conditions, to ascertain how they manage. Re-member in pot culture, air must reach the roots or they will die. The potting mix must be allowed to dry to a depth of 25 to 50 mm (large containers) before further watering is needed. While plenty of water is required, more plants are lost through over-watering than by any other factor. When water is given, surplus water must flow freely from the drainage holes in the container; by over-watering we are referring to the too frequent watering of the plant, and the associated exclusion of air reaching the roots.
 

 


Site established 9th May 1998