Many varieties of the
orchid can be grown fairly easily in a common windowsill. Others require a good
deal of humidity to grow properly. It is not true that one needs a greenhouse
to grow orchids. Many orchids even grow well without a greenhouse given proper
light and water.
In nature, orchids can
be divided into four types according to growing conditions. Most are classified
as epiphytes found in tropical moist broadleaf forests or mountains and
subtropics. These are anchored on other plants, mostly trees and shrubs. The
rock growers, or lithophytes, cling to the surfaces of rocks. Saprophytes are
those that grow in mulch, often on the forest floor. Finally, there are the
dirt growers, or terrestrials, which anchor themselves in soil or sand. A few
are lithophytes, similar to epiphytes but growing naturally on rocks or on very
rocky soil. They derive their nutrients from the atmosphere, rainwater, litter,
humus and even their own dead tissue.
The structure of the
leaves corresponds to the specific habitat of the orchid. Species that
typically bask in sunlight have thick, leathery leaves. The laminas are covered
by a waxy cuticle. These retain their necessary water supply. For shade
species, the leaves are tall and thin. They cannot tolerate a drop in
atmospheric humidity or exposure to direct sunlight. Between these two
extremes, there is a whole range of intermediate forms. The leaves of some
species can be most beautiful. For example, the leaves of the Macodes
sanderiana, a semiterrestrial or lithophyte, show a sparkling silver and gold
veining on a light green background.
The sepals form the
exterior of the bud. They are green at this stage, but sometimes, if the orchid
blossom is purple, the buds can show a purple tint. When the flower opens, the
sepals become intensely colored. In many orchids, the sepals are mutually
different and generally resemble the petals. It is not always easy to
distinguish sepals and petals. The reproductive organs in the centre have
adapted to become a cylindrical structure called the column. On top of the
column lies the stigma and the pollinia, a mass of waxy pollen on filaments.
If pollination is
successful, the sepals and petals fade and wilt but they remain attached to the
ovary. The ovary typically develops into a capsule. The ripening of a capsule
can take 2-18 months. The microscopic seeds are very numerous, over a million
per capsule in most species. They blow off after ripening like dust particles
or spores, barely visible to the human eye.
Orchids are indeed some
of the most beautiful flowers in the world. Breeding them can be a highly
challenging endeavor. It needs a lot of patience because the orchid seeds are
characteristically small and mortality rate of both the seeds and the sprouts
is high. The National Orchid Garden in the Singapore Botanic Gardens is
considered by some to be among the finest collections of orchids in cultivation
open to the public. The Taiwan Orchid Plantation was set up to develop
commercial orchid exports in the future.
Orchids have become a
major market throughout the world. Buyers now bid hundreds of dollars on new
hybrids or improved ones. Due to their apparent ease in hybridization, they are
now becoming one of the most popular cut-flowers on the market. Though orchid
hybridization has been happening for many years, only recently has new
technology made it into what it is today.
Summary: Orchids are divided
into four types. They are epiphytes found in tropical moist places, lithophytes
which grow on surfaces of rocks, saprophytes and terrestrials, which anchor
themselves in soil. The structure of the leaves corresponds to the habitat.
Species that bask in sunlight have thick, leathery leaves. The shade species
have tall and thin leaves. When the flower opens, the sepals resemble the
petals. So it is not always easy to distinguish them. The reproductive organs
are in the centre and have adapted to the column. On its top are the mass of
waxy pollen. They are numerous and blow off after ripening. Orchids are indeed
beautiful flowers. Breeding them can be highly challenging as it requires
patience. They have become a major market throughout the world.
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