By JAMES TABABA
Orchids come from the large family Orchidaceae and are known for their exotic-looking flowers. They have a distinct flower structure that differs from other blooms. Orchid flowers have four main parts – the sepal, petal, lip or labellum, and column.
For most flowers, sepals are the green protective part that covers the flower bud before they bloom. With orchids, however, sepals look very similar to the petals. Orchid flowers have three sepals. One is located at the top and is called the dorsal sepal; and the other two, found at the lower part of the flower, are called lateral sepals.
The petals also always come in threes. The first two lateral petals look like sepals and the third petal is a modified structure called the lip or labellum. It is located at the lower portion of the flower and usually marked with a different pattern or color and shaped differently to attract pollinators. The labellum also serves as a landing site for potential pollinators. The last part is the column. It is the finger-like part that protrudes from the center of the flower.
Unlike other flowers, orchids have a fused male and female reproductive system. The top part of the column has the male (stamen), the part containing the pollen while the bottom part is the female (pistil), having a sticky cavity for collecting pollen.
Another distinguishing characteristic is that the flowers have bilateral symmetry, meaning one side will mirror the other if the flower is cut in the middle from top to bottom.
Most flowers reward their pollinators with nectar to attract them and encourage pollination. Since orchids don’t produce nectar, they use their colorful flowers to attract small birds and butterflies. Some orchids even copy the scent of rotting meat or the smell of insects to attract pollinators.
There is a popular belief that orchids are parasites because they are commonly seen attached to stems and branches of trees. The truth is that they are not parasites but epiphytes. An epiphyte is a plant that grows on top of another plant. They only cling to trees as support. They do not take any nutrients from the tree because they can get their water and nutrients from the air.
There are also orchids that grow on the ground. They are called terrestrial orchids. These orchids tend to be hardier and easier to take care of than the epiphytes.
Orchids can be classified into two depending on their growth habits–monopodial (vertical growing) and sympodial (horizontal growing). Monopodial orchids are orchids that grow from a single upright stem. The flower stem or spike emerges from the base of the upper leaves. Phalaenopsis and vandas are examples of monopodial orchids.
On the other hand, sympodial orchids grow horizontally through rhizomes. Rhizomes are bulbous stem-like structures extending along the surface of the potting media. Sympodial orchids have a unique structure called pseudobulbs. These structures are thick stems, usually pod-like, that grow directly below the leaves. Pseudobulbs serve as food and water reserves during drought conditions. Sympodial orchids can be propagated through the pseudobulbs. Examples of sympodial orchids are dendrobium, cattleya, and oncidium. Monopodial orchids do not produce pseudobulbs.
READ: How the Philippine most common orchids differ from each other
Orchids are recognized by their distinctive structure that sets them apart from other ornamental flowers. Understanding their characteristics and growth habits is necessary for properly managing the plant. For example, repotting monopodial orchids is easier and more straightforward because they have only one stem, unlike sympodial plants that grow multiple rooting systems. Moreover, monopodial orchids need frequent watering because of the absence of pseudobulbs that store water in sympodial orchids. Consider these management practices if you have plans to grow your own orchids.