Orchids can be divided into two main parts. The stem and root system make up the lower part of an orchid. While they are not as showy as the flower, they are essential. The flower of an orchid is known as the inflorescence. It contains sepals, petals and the plant's reproductive system.
The roots of an orchid serve various functions. Some orchids are epiphytes: plants that use their roots to attach themselves to another plant or surface. Located on the roots are smaller hair roots that help the main roots absorb minerals and water. Roots also can contain pseudobulbs, which are thickened stems designed to absorb and store water.
Stem and Spike
The stem and spike connect the flowers and leaves to the root of an orchid. Stems may be fragile or sturdy depending on the orchid. Within the stem are small passageways called veins that carry water and nutrients between the roots and the leaves or flowers. Similar to the stem is the spike, which bears the buds and flowers of an orchid. Spikes can produce one flower or a cluster of flowers.
Leaves grow on the stem of an orchid and are a good barometer for how healthy the orchid is. A healthy orchid will have leaves that are bright green, smooth and firm. Dark green leaves indicate that the orchid is not getting enough sunlight. Orchids also can have modified leaves known as bracts. Bracts are colorful and grow around the flowers or stems.
The flower of an orchid appears to have five or six "petals." Actually, only the inner three are petals. The outer two or three are known as sepals. The top sepal is known as the dorsal. The other two are lateral sepals. Of the three petals, the bottom is called the lip or labellum. It is usually a curved shape and a brighter color than the other petals. These differences are used to attract insects that will pollinate it.
The column is the fused sexual organ found above the lip of the orchid. It contains both the female and male parts. Inside the column are the anther, which carries the pollen, and the pistil, which receives the pollen and bears the seeds.