Cymbidium orchids are the larger growing and more physically substantial orchid plants often seen growing outdoors in temperate climes. They produce multiple large waxy flowers in very muted hues on thick green stems over thin strappy foliage. Unlike many orchids, cymbidiums need a marked cool period for 6 weeks to 2 months in the fall to set the bloom cycle in motion and produce buds. Provide this needed cool treatment along with other basic cultural requirements of orchids and repeat annual bloom can be yours.
Water your cymbidium weekly with tepid water soaking the planting medium and allowing excess to drain away. Feed once per month with a water-soluble orchid food diluted with water using 50 to 75 percent of the recommended amount of fertilizer. Mist your cymbidiums daily to raise the ambient humidity of their growing space to between 50 and 80 percent.
Provide a growing location with very bright indirect light or filtered direct sunlight daily such as would be obtained in a mesh or lath grow house. Cymbidiums require more light than most other orchids and will not bloom properly or at all where there is insufficient sunlight.
Ensure daily ambient temperatures between 65 and 70 degrees F and evening and night temperatures hovering between 58 and 60 degrees F. Temperatures that are consistently warmer or colder run the risk of stressing or damaging the plant and upsetting bloom.
Plan an annual cold-set period for your cymbidiums in the fall to prepare them for bloom. Store the orchids outdoors or indoors where the overnight temperatures hover between 35 and 50 degrees F. Leave them in this location for 6 to 8 weeks and then return to normal conditions. Smaller mini cymbidiums need only 60-degree-F overnight temperatures to set bloom and should not be exposed to near freezing temperatures.