Oncidium [ON-sid-ee-uh m]
The Oncidium orchid genus is one compromised of a great many specifies with an equally diverse range of habitats. From the high elevations of the Andes, to sea level in New World tropics from Florida and Mexico to Central and South America, the Oncidium is found almost entirely in these areas. Several hundred species exist but across all their distinctive shape of their petals create a sight that may not easily be forgotten.
First described in the 1800s by Olof Swartz, a Swedish botanist and taxonomist, its name is derived from the Greek word “onkos” meaning swelling which refers to the callus at the lower lip.
As the dominate component of many Oncidiums, the lip quite resembles a fleeted skirt adorned on a “Dancing Lady” - as it is so affectionately referred to today. Their skirts are painted shades of yellow, brown, red, white and pink and are often edged with a frilly pattern. The large lipped flowers are produced in great number and fall gently on stems amongst rather prominent pseudobulbs and somewhat thin leaves. Their stage: a thin long stem that can stretch from three to five metres in length creating quite a show for passers-by.
On show all year round the “dancing ladies” have no particular preference for where they perform. Found from hot and humid tropical lowlands to the cool hazy mountains and even across to the arid and almost desert-like climates, the dancers have one main condition that their stage is dressed in suitable light.
Most specifies of Oncidium genus are epiphytes which means that they grow harmlessly upon other plans. Without its roots sunk into ground and soil, the Oncidium absorbs the nutrients and moisture that it needs to survive from the air and rain. Amongst other species of Oncidium you will find that they prefer to grow on rocks and on the ground among the leaf filter.
The Oncidium loves to show off and if taken care of, with continue to do so throughout the year and with new pseudobulbs. The Oncidium will product new branches almost immediately from a new pseudobulb where with other Orchid this can take up to a year. It is important to know that once a pseudobulb has grown a new stem it will not produce again from the same pseudobulb. The Oncidium is a truly graceful dancer that revels in gracing the dwelling of its admirers, take care to observe and preserve their bloom and you will not be left wanting.
How to Grow (South Africa)
60% to 70% filtered sun for full day. If growing indoor, find a bright place but without direct sunlight.
As a general rule plants with heavy thick leaves should be watered less and allowed to dry out between waterings. Plants which have thinner softer leaves must not dry out completely before you water again. Most of these plants are epiphytes, i.e. they grow on the branches of trees, although unlike parasites, do not obtain nourishment direct from the host tree.
Oncidiums should be kept indoor in winter and autumn; they can grow outdoor in warm seasons.
The species all originate from South, Central and North America and occur from sea level to altitudes of 3000m above sea level in the Andes Mountains which equates to a range of temperatures from 35 to 25 degrees Celsius maximum and 20 and 8 degrees Celsius minimum to grow and flower well.
High humidity helps the growth of leaves and stem of Oncidium, it stops its activity if environment is very dry.
The ascending growth habit together their epiphytic nature makes pot culture difficult as the plant as well as the roots will grow outside the pot. The Oncidiums are ideal orchids to mount on trees in the garden or mounts that you can hang in your shade house. This group of orchids needs a good open mix as their roots rot easily when waterlogged. Repot after flowering, when root tips are still green and active into squat pots.
Regular applications of foliar feed fertilizer are needed for plump speudobulbs especially when in bud and flower as this drains the plant to the extent that some will flower themselves to death.
Repotting can be done in spring, need lots of water and fertilizer in summer, bloom in autumn and possibly other seasons.