Oncidium Orchids (a rich cocoa scent) at home.
Oncidiums are popular indoor for a very good reason, their large sprays of flowers often sag with dozens of blooms. They have been freely hybridized. There are actually several hundred recognized oncidium species, but the naming is not stable, so there is considerable flux as experts reclassify plants.
The most common oncidium grow well under normal indoor conditions. They have large pseudobulbs (a bulbous thickened area of the stem) that come up from a mass of thin white roots. The large leaves can get up to 2 feet long and emerge from the pseudobulbs. The oncidium flowers in fall.
Oncidiums are magnificent in bloom. A large, well-grown plant might yield six or seven-branched sprays of yellow flowers. The effect is very much like a cloud of buttery butterflies. The most popular species include O. leucochilum, O. longipes, O. sarcodes, O. pulchellum, as well as many hybrids. Although oncidiums are known for their yellow flowers, other varieties are available. The O. Sharry Baby is sometimes called the chocolate orchid for its sprays of brownish flowers with a rich cocoa scent.