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2. THE FOOTHILL
MONSOON FOREST HABITAT
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This is perhaps the most important of all the orchid
habitats, with some 60% of all orchid species found in this zone, mainly the sympodial types familiar to most orchid
growers. The orchids found include many cymbidiums, dendrobiums such as nobile and fimbriatum, coelogyne, many
oncidiums, lycaste and sophronitis, and the single flowered plain green leaved paphiopedilums.
This habitat is found along the Brazilian coastal mountain ranges, the foothills of
the Himalayas, the mountains of Burma, Malaysia, Indochina and Mexico, and the eastern slopes of the Andes, at
higher elevations than Habitat 1. Typically it falls within the altitude range of 850 to 1850 metres above sea
level.
The habitat is characterised by the following features.
- It is cooler than the Lowland Rainforest habitat discussed earlier.
- It is subjected to heavy rainfall and markedly increased seasonal variation. Annual
rainfall up to 4000 mm per annum is common n the Serra de Cubatao in Brazil, with falls of 1300 to 3500 mm are
experienced within the Himalayas. Typically there are morning mists and clouds and a fully saturated atmosphere.
The morning sunshine and breezes dry the plants by 8 to 10 am, with the substrate dry by midday. Clouds and mists
form again late in the day, with the forest quickly becoming fully saturated by late afternoon.
- Winters produce little direct rainfall, although humidity remains high.
- Typically skies in winter are clear, with bright sunshine.
- Summers are wet and shaded, with many days of cloudy conditions..
- In the mountains there is constant air movement, with orchids rarely found where
calm conditions are experienced.
Some weather data is available for a typical cymbidium habitat in Sikkim, North India,
at the upper altitude range for this habitat. The greater variability in temperatures from the earlier habit should
be noted, together with the diurnal range of 4-8oC.
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Rainfall is dominated by the summer monsoon, which can occur from early summer to autumn.
In two habitats, one in Sikkim India and the other in Burma, at different altitudes, the majority of rain can be
seen to fall over the summer months the actual period dependent on the timing of the arrival of the monsoonal conditions.
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. Humidity remains relatively high, between 60 to 90% at Sikkim, with the highest
levels during the summer, but still with significant levels of humidity during the winter months.
This habitat experiences more bright days than that first discussed, especially during
the winter and early spring. During the summer only 1 day in three receives even 2 yours daily sunshine.
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If one can categorise the typical climate features for this habitat, temperatures usually
range from 10-25oC, with a typical maximum range of 5-32oC. The diurnal temperature variation is slightly higher
than Habitat 1, being 20oC. The maximum temperature differential throughout the habitat is 27oC. Humidity typically
lies between 60-90%.
Essential cultural basics for plants from this habitat revolve around allowing for
the pronounced seasonal variation many are used to in their natural homes. Many have distinct seasonal growth pattern,
with new growths broken in the spring, followed by a period of rapid growth, with maturity in the early autumn,
and then relative dormancy during the winter months. Flowering and successful continuing culture requires that
this growth cycle be allowed to progress naturally.
A feature of the habitat is the bright dry winters and warm wet dull summers coinciding
with the summer monsoonal conditions. For some plants the bright light during winters seems important for the proper
maturing of the previous seasons pseudobulbs. The need for good air circulation all year is also an important component
of their culture .
  
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