Origin of Orchids
Orchids are not that difficult to grow if you know where they come from. The trick is to replicate their native environment in your home.
Some orchids bloom in the winter because they are native to the southern hemisphere; others are fragrant only in the evening in order to attract the nocturnal birds and insects they needed for pollination.
Orchids
‘Nothing is more extraordinary in the history of the vegetable kingdom, as it seems to me, than the apparently very sudden and abrupt development of the higher plants.’ -- Charles Darwin
Darwin was fascinated by orchids. In his Origin of Species he mentioned the ‘inexhaustible number of contrivances’ by which orchids ensure their pollination, pointing out that these would have entailed changes in every part of the flower.
Care and Maintenance of Orchids
The three key components to growing orchids are humidity, water and soil conditions. Different varieties of orchids have different preferences about climate, nutrients and water. Again, it is important to know the native environment of the particular species being grown.
Most orchids thrive in about 60% humidity. Indoors, they may need help in the form of a nearby saucer filled with rocks and water, or a humidity tray.
Orchids grown indoors often require a special orchid fertilizer, and a special potting medium to help them grow.
How To Repot Orchids
When you repot an orchid plant, your intention should be to provide new and fresh media rather than just a larger pot. Most orchids do not grow well in too large a pot, as they will concentrate on root development and stop growing upwards.
How Orchids Mimic Insects
Orchids come in many shapes and sizes, the best known probably being the insect–mimicking species. Many of these mimics have very ingenious ways of attracting pollinating insects, appealing to the senses of both sight and smell.
One of the most amazing of these mimics is the Bucket Orchid, which comes in two species, Coryanthes speciosaand Stanhopea grandiflora. Bucket orchids are pollinated by the males of two species of bee — Euglossa meriana and Euglossa cordata — which themselves are specially designed for the task.
Attracted by the smell of nectar emanating from the orchid, the bee gathers from the surface of the flower a liquid which will make him attractive to female bees.
The surface of the orchid is slimy, which causes the bee to slip and fall into the ‘bucket’ that contains a pool of liquid dripping from a gland above. The only way the bee can escape is through a tunnel, and there is a convenient step leading from the pool of liquid to the tunnel entrance.
As the bee is about to escape from the tunnel, the walls of the tunnel contract, gripping the bee. The plant’s mechanism then glues two pollen sacs to the bee’s back. After allowing time for the glue to dry, the bee is released. If the bee then flies to another bucket orchid, the same process will take place, except that this time, when the bee attempts to leave the tunnel, a hook in the roof of the tunnel removes the pollen sacs, and the fertilization process is completed.