How to Grow Cymbidium Pseudobulbs

Pot the cymbidium orchid in a commercial potting mix formulated specifically for orchids. Pseudobulbs must rest on top of the potting mix; don't bury them beneath the soil.

Place the cymbidium in bright but indirect light, preferably near a window with an eastern exposure. Sunlight filtered through a gauzy curtain or dappled with shade from taller houseplants is ideal.

Monitor the cymbidium carefully to check it is receiving the correct amount of light. According to the National Gardening Association, the foliage should be a bright yellow-green color. Dark green leaves indicate insufficient light, while yellow foliage indicates too much.

Maintain daytime temperatures of 50 to 85 degrees Fahrenheit; nighttime temperatures should be between 45 and 55 degrees Fahrenheit. Cymbidium orchids -- indigenous to the mountainous regions of Asia and Australia -- are unable to tolerate high temperatures and do best in cool nights.

Keep the soil evenly moist, but not saturated. To prevent root rot, empty the saucer after watering.

Use a humidifier in the room to provide the moist air cymbidiums need.

Feed cymbidiums with a high-nitrogen fertilizer every 10 days in March through October. According to the National Gardening Association, a 22-14-14 fertilizer formulation is ideal. From August through October, use a low-nitrogen fertilizer in a 0-10-0 NPK formulation.

Re-pot the cymbidium when its pseudobulbs become so numerous that they crowd the pot. Do this when blooming is finished for the season. To harvest pseudobulbs for a new orchid planting, divide them with a sharp knife, taking at least three healthy pseudobulbs with the roots attached for the new orchid.

Place the new division in the potting soil in a new container, with no more than 2 to 3 inches between the pseudobulbs and the pot edge. According to the National Gardening Association, they prefer being closely packed.

Water well, and place the plant in a shaded area. The new orchid will normally root within 10 weeks.

Examine the pseudobulbs regularly for signs of pythium root rot, which causes the bulbs to rot and shrivel. Remove affected pseudobulbs by cutting them away at the connecting axis with a sharp, clean knife, then re-pot the cymbidium in a new potting medium. You can treat root rot with an antifungal mefenoxam.