Friday 21 March 2008

WHAT ARE ORCHIDS?

Orchids form the world's largest family of plants. They grow wild in every country except Antarctica. The flowers of orchids appear to be very complicated, but in reality they are based on a very simple structure. Like many of their relatives such as the lily family orchids have three sepals and three petals. However, this similarity with other plants is only superficial as all orchids have their middle petal transformed into a unique structure called the labellum or lip. This petal is always quite different from the other two petals. Orchids also have a different reproduction feature. Instead of separate male and female organs, the stamen and pistils, these are combined into a single structure called the column.

Orchid seeds are like tiny dust specks. They are placed in sterile flasks in a mixture of sugar and nutrients. The flask acts like a tiny greenhouse. The seedlings remain in the flask for about a year. They are then moved to a community pot. They grow in the pot for eight months to a year. They are then moved to individual pots. It can take up to seven years to grow a mature blooming plant, depending on what type of an orchid is being grown. Orchid species have developed blooms to entice the insects that pollinate them. They also control when their fragrance is at it's peak. Some orchids' fragrance is best at night, therefore they are pollinated by night flying moths. Terrestrial orchids grow in meadows, woodlands, and on mountain sides.


Orchids not only grow in tropical rain forest trees, many species actually grow on rocks (they use the rock as an anchor - something to hold on to for support just like their tree-living cousins).