Cymbidium

--- RECOMMENDED CULTURE GUIDE PER THE AMERICAN ORCHID SOCIETY ---
Temperature: 1) Large flowered species from China and the Himalayas require a pronounced period of cool weather during the late summer and early fall such as coastal California to initiate flower spiking, maximum night temperatures of 53°F (12C).

2) Small flowered terrestrial species from the Himalayas, China and Japan do not require a substantial chilling period to bloom. These do well in cool to intermediate temperatures year round.

3) The small flowered tropical species require no chilling period and prefer to be warm year round.
Light: Anything having ancestors from the higher elevations will need high light intensities to grow and more importantly, flower freely. Cymbidiums are quite happy with between 5000-6,000 ft. candles (about 50% shade) of noon light and can take direct sun either in the early am or late pm. However, they do not enjoy full sun all day except maybe in coastal areas of California. As flower colors fade in this light it is quite acceptable to add extra shade over actual blooming plants or take them indoors when blooming for a month or so and enjoy the blooms. Most failures with re-blooming Cymbidiums can be traced to inadequate light.
Water-Humidity: Watering and fertilizing: Cymbidiums enjoy copious water during their summer growth but also have substantial pseudobulbs to store moisture so don’t suffer if left up to 10-12 days between waterings in the depth of winter, especially in higher latitude regions. Always water well, making sure the pot is fully saturated and then let dry out before the next watering.
Fertilizer: Cymbidiums are heavy feeders in their growth periods and much less over winter. Some hobbyists achieve very good results by using slow release fertilizers like Nutricote as topdressing twice a year. This product is sold under various trade names like “Dyn-O-Mite” in one-pound containers. The 13-13-13 formulation that is good for 180 days is very satisfactory. Apply it twice a year in early spring and again six months later. It is recommended to apply a heaped teaspoon per 6-inch pot in spring and a level teaspoon in fall with more or less for bigger or smaller plants. If you prefer to liquid feed, use 20-20-20 year round, at recommended strength in summer and fall and at 1/3 recommended rate over winter into spring. Many growers topdress their plants with a heaped teaspoon of Epsom salts (MgSO4) in June and again in mid-August in the northern hemisphere.
Potting: Cymbidiums are semi-epiphytic so enjoy any growing medium that is free draining. Many growers use a mixture of coconut chip, bark and perlite that is supplemented with dolomitic lime to bring up the pH. Dividing and repotting should always follow flowering but not until the new shoots are about 5-6 inches long. Potting up to a larger size pot when the rootball is in good condition can be done at any season except winter. The large flowered species are usually grown in large pots or tubs; the small flowered terrestrial types bear upright inflorescences and are best grown in pots; the small flowered tropical cymbidiums mostly produce pendent inflorescences and should be grown in hanging baskets or pots