Cymbidium are monocots in the orchid family Orchidaceae (Krunchid, 2007) and they are sympodial and pseudobulb as Cattleya orchid. (Rapee, 1973) Cymbidium is widely popular genus of 44 species and 19 species found in Thailand most have beautiful flowers. (Kanjana 2012) Highland and low temperatures are important for growing Cymbidium, Nowadays have been breeding hybrids that can be grown in high up temperatures area.
Thailand is number one of the source of production and export orchids when compare export value. The export volume of orchid about 29.5 million tons include the Cymbidium orchid about 7 million tons. (Krunchid 2007) So, Cymbidium orchid are important in the economy of the country, with diversity of species, the form of flowers are different inflorescence, color and size. Some species have strong inflorescence. The highlights of Cymbidium orchid is flowers blooming form 3 weeks to 1-2 mouth. (Nuttha 2004) If cymbidium can control the flowering, it will beneficial to Production and export. Therefore, studies the substances can promote the growth and flower induction by using Gibberellin is group of plant growth regulators. Sometimes gibberellin can replace low temperature for flowering and promoting cell elongation in the inflorescence some species. (Danai 2001) Potassium Chlorate using induct flowering in longan because it can stimulate ethylene for flowering. (Tanachai 1999) To be suggest in the production of Cymbidium orchid.