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Standing
in front of the display window of a flower shop
in a cold climate country, everybody is fascinated
by the single orchid flower standing in a slender
vase. The shimmering dispersion of colours and
the elegance of their shape let us think of
warm, humid days in the tropics, where this
flower belongs to. Orchids have always held
a fascination for people; there is an air of
mystery surrounding them. Mention the word "orchid"
and terms such as exotic, rare, expensive, beautiful,
colourful and unique will arise. Everyone will
have a different perception and all of these,
no matter how diverse, will be correct.
With more
than 27 000 species, orchids are the largest
family in the plant kingdom. Much bigger is
the number of hybrids, from which more than
50 000 have been described. Many of these hybrids
are important commercial plants that are used
as cut flowers and potted plants to satisfy
strong demand, both locally and internationally.
With the exception of glacial regions and arid
deserts, orchids grow all over the world, even
on Greenland some species can be found. In the
tropics they are numerous and colourful and
are often seen as characteristic of the region.
In Thailand alone 900 different orchid species
can be found.
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Orchids have
their own unique characteristics and charms.
The mere fact that their roots live on air is
enough to make us wonder how they can sustain
themselves. The roots of the orchid are different
from those of other plants, consisting of a
special sponge-like layer of tissues called
velamen that covers up the true roots inside.
This special sheathing acts as a moisture collecting
device while protecting the roots underneath
from direct sunlight.
We can categorise
orchids by looking at their growing habits.
Many have roots which grow into the ground or
dirt like most other plants (terrestrial). Another
group has roots which grasp and cling to trees,
without in any way harming or taking away food
from the host (epiphytic), and those who find
unusual places to grow such as in the crevices
of rocks on the side of cliffs (lithophytic).
In the tropics,
most species can be found on trees in the upper
canopy of the rain forests, where humidity is
high year round. In regions, which have a distinct
precipitation and temperature cycle, orchids
have adapted to the dry period by storing water
and nutrients in the swollen lower part of the
stem, the pseudobulb. Other orchid species form
succulent leaves which serve the same purpose
and help in reducing the loss of water by evaporation.
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What makes
orchids different from other flowering plants?
The flowers are, what clearly distinguish orchids
from other plants: Some bear large flowers of
bright hues, and some have smaller or even tiny
little flowers of softer tones. They may flower
singly or in small groups of two or three per
stem. Others will bloom in a big cluster or
a bunch with some standing up on an erect stem
and yet others bending down in a flowing cluster.
The scent of orchids also differs, ranging from
those without any smell to a soft and subtle
scent through to a more full-bodied and pungent
fragrance.
Each orchid
flower has two sets of petals consisting of
three outer and three inner ones. While the
outer ones are similar to each other the three
inner petals will usually consist of an identical
pair and a singular one that is unique in size,
shape and often also in colour. This petal is
called lip or labellum, and is almost always
highly modified and quite different from the
other segments in size, shape and colour. This
structure often plays an important part in orchid
pollination. Pollinators, such as bees, wasps,
butterflies, moths, flies, beetles, ants and
even birds are attracted by form, colour and
often fragrance.
When the
pollen comes in contact with the stigma, the
bloom will rapidly wither and the ovary will
expand into a pod. As maturity peaks, the full-grown
pod will burst open longitudinally and the mass
of dust-like seeds inside will be distributed
into the air. Some of these pods can contain
up to 4 million seeds, depending on the species.
The seeds will be air-borne until, with great
luck, some land on a host tree. As the seeds
lack any nutrients, they depend on a specific
kind of fungi (mycorrhiza), which is essential
to help in finding food during the first part
of the seedling's growth until it can mature
into another orchid plant. The mortality rate
in the wild is enormous.
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For this
reason, cultured orchid seeds start their life
in the sterile atmosphere of laboratories on
a special nutrient-rich culture medium. This
technique has made it possible to produce large
quantities of both species and hybrids in a
sterile environment. Today, the most attractive
orchid species are entrenched in cultivation
and have been propagated by division or by seed.
Depending on the genus or kind, orchids can
take from twelve months to twelve years from
germination to flowering. Most wild orchids
flower only once a year and the shape or form
of their blooms are not as popular on the market.
Wild orchids are usually raised only by enthusiasts,
who truly love the natural looks of these "miniatures"
or "botanicals", as they are known.
While the
collecting of popular species from the rain
forests can threaten the survival of wild orchid
populations, their main enemy is habitat destruction.
Southeast Asia is one of the world's most densely
populated regions, and its virgin forest continues
to be cleared and burnt. New species continue
to be discovered, and a number of "lost" species
have been relocated. Yet one wonders how many
species, both plant and animal, have become
extinct before they have even been recorded.
On Lanta
Island, Lanta
Orchid Nursery has specialised in cultivating
the native orchids from all regions of Thailand.
More than 100 species of the more than 900 native
to Thailand are on display. Lanta Orchid Nursery
is located in the mountains above Lanta Long
Beach, opposite Sumate Elephant Trekking. It
is open from November to April daily from 09:00
to 17:00.
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