Of all the orchid genera, the Cymbidium orchid is one of the easier to care for, particularly if you want your orchids outside for much of the year. Because most commercially available Cymbidium orchids are terrestrials, they must have special, loose media to grow in. Typically, they thrive in a medium or fine fir bark mix or a specified Cymbidium potting mix.
Cymbidium Care Basics
These quick tips are followed by more in-depth information about pruning and propagating Cymbidium orchids as well as specific care instructions for each phase of its life cycle.
Light: Cymbidium orchid light requirements include: morning sun or afternoon sun, with protection from the hot mid-day sun. A light-green leaf with just a hint of yellow indicates the maximum amount of sun the plant can take, and a dark-green leaf indicates not enough sun.
Temperature: Cymbidiums will tolerate considerable summer heat as long as they get cool, mild night temperatures –between 50-65°F. Cold weather, even down to 30°F for a few hours a time or two, will not damage an acclimatized plant. But once the plant spikes or flowers, it should be protected from temperatures below 35°F. Regardless, plants should always be kept free of frost.
Water: Watering should be done frequently, sometimes twice per week during the summer months. Fertilize during 3 out of 4 of those irrigations. Always keep potting soil moist, but not wet or soggy. Decrease watering Cymbidium and increase air circulation during the dark periods.
Fertilizer: High-nitrogen fertilizers should be used from February until July, while low nitrogen fertilizers should be used from August until January. Use high nitrogen (30-10-10) fertilizer, but mix it only half-strength. Use a low fertilizer (6-6-30) diluted to ½ strength September through January. Keep in mind the specialized Cymbidium fertilizer is available in many garden stores.
Growth: Cymbidiums may not get very much taller, but more leaves and pseudobulbs will grow.
Blooming: From late December through May and last one to three months.
Re-potting: Re-pot Cymbidium every two to three years from February to June with a well-draining medium. Fine bark is suitable in mild summer climates, while a finer medium such as Super Orchid Mix works well in warmer summer areas.
Planting Outside: Terrestrial orchids, Cymbidiums can tolerate straight potting soil; they seem to do best on a rich, well-drained medium, however.
USDA Gardening Zones: 5-10
Cymbidium Orchid Care by Life Cycle Phase
- blooming phase: late fall to winter in the northern hemisphere, keeping its blooms until spring
- growing phase: spring through early fall
- dormancy: fall – winter
Blooming Phase Cymbidium Care – February – June
What’s happening: flower spike emerges from the base of newest pseudobulb.
What to do: At 6 inches, put a skewer or stake in alongside the spike and gently tie it. Green garbage bag ties are good enough. Unlike its cohort the Phalaenopsis, the Cymbidium orchid benefits from fertilizer year round. As mentioned above, use a fertilizer with high-nitrogen (30-10-10) content to provide the best Cymbidium winter care from February until July, while low nitrogen fertilizers (6-6-30) should be used from August until January. Always dilute with water by half as most labels instruct.
As the cold-tolerant Cymbidium may be outside when it flowers, be sure to watch for the little holes or full-bore shredding that can indicate your plants have been invaded by pests.
Growing Phase Cymbidium Care after Flowering– March – August
What’s happening: The Cymbidium will bloom anywhere from three weeks to two months. When the pseudobulb matures in the fall, keep plant outside when it’s not raining. The cold night air initiates flower spikes.
What to do: Before pruning, make sure all of the many blooms have fallen off and the entire stem has turned brown. At that point, cut the stem at its base. Use a high nitrogen fertilizer from February to July during this growing phase to support the leaves.
Because Cymbidiums do their best when they experience a significant temperature drop from day to night, experienced growers often keep them outside in all frost-free months.
Care of Cymbidium Orchids When Dormant – September – January
What’s happening: Almost like people, orchids need a chance to regroup before bursting from the gate with their year’s best performance, the bloom. In fall, the leaves will stop growing as the plant’s energy is diverted toward the creation of that winter’s bloom. In other words, much is going on beneath the surface.
What to do: Reduce watering at this point and place the plant in a cooler, darker area for several weeks to signal the cooler season required to signal winter. A north facing window can work. Use a low nitrogen fertilizer September through January once a month. Use low nitrogen fertilizer form August until January to give the plant a rest. High nitrogen causes rapid foliage growth at the expense of the bloom. Different levels of the three components of fertilizer (Nitrogen, Phosphorous and Potassium) signal the plant to expend its energies to specific parts of the plants. Nitrogen fuels growth of the fronds. Phosphorous revs up the blooms, and Potassium targets the roots. Keep media barely dry to almost moist throughout the winter.
What’s happening: While Cymbidiums actually like to be crowded, when the potting material has deteriorated, shoots hang out over edge of pot or the pot actually splits, it’s time to move the plant to a bigger pot. This typically occurs every two years.
What to do: Only repot in spring after blooming. Consider separating Cymbidiums into separate pots if you want to give plants away or start a new batch in a new area. Water new Cymbidium potting mix thoroughly and drain it before starting the repotting process. Never repot an orchid in a pot more than one inch larger than the original. A large pot may inhibit future blooms.
Materials: medium or fine fir bark; clay pot just one inch larger than original (“over-potting” can reduce bloom initiation and growth); Clay pots allow for more aeration than plastic and the Cymbidium needs to dry out. Use sharp, sterilized scissors or secateurs.
- Moisten your potting mix
- Gently pull plant from original pot and shake all potting mix from roots.
- Trim dead or damaged roots.
- Work apart roots under pseudobulbs if you plan to divide plant. When cutting through roots, include a “back bulb,” a bulb without a leaf, along with two or three bulbs with leaves. While pseudobulbs divided and planted singly will continue growing, you won’t have a flower that year.
- Create a cone of potting mix in the pot or pots.
- Gently arrange the roots around this cone.
- Fill the rest of the container with the mix, working it between the roots.
- Fertilize and water, allowing to drain.
Growing Cymbidium Outdoors
Cymbidiums can withstand high temperatures in the summer without wilting, and they do well outdoors in humid climates in the summer. Make sure to measure the temperature so that it’s no more than 85° in the shade. Leaves should be apple green rather than dark green. If they are dark green, it may mean they aren’t getting enough sunlight to feed the rhizomes (thick roots) which eventually produce the bloom. Make sure to water liberally during the summer and fall. As mentioned above, Cymbidiums need a significant temperature drop overnight to really thrive.
Dividing and Propagating Cymbidium Orchids
Large, mature Cymbidium plants develop a structure called a backbulb at the bases of their fronds close to the regular pseudobulbs. Brown and papery, these storage structures have no leaves. If given a “rest” in a cool, dark place, they generally sprout new growth.
Follow these steps:
- Gently remove the backbulb from the potting mix.
- Remove any leaf bases or roots.
- Put Cymbidium backbulbs in a cool dark place for three weeks or more.
- When new growth begins from the base, put bulbs in open plastic bags to retain moisture. Move from cool garage or refrigerator to room with higher temperature.
- Once the new stem is about an inch long, repot bulb in 3” or 4” pot. Orient the new growth toward the center of the pot.
- Water only lightly until the new growth starts to form its own roots. A bulb will begin forming on the new growth.
- It will be two to three years before this new plant will flower.
- Cymbidium Orchid Care Conclusion
Unlike the tree-climbing Phalaenopsis, the Cymbidium orchid stayed right on the ground, evolving in decaying leaves and other debris on the ground beneath the trees in the cool Himalayan Mountains of India and China. This climate produced a shade-tolerate orchid that thrives on significant moisture and cool night-time temperatures. Keep it in porous, fast-draining soil and watered often. Make sure you allow it that dry rest in the winter time so it can prepare to bloom come February.