Water the Cymbidiums
Cymbidium are orchids with pseudobulbs, which produce clumps of long leaves; the head from which the plant originates tends to gradually widen, becoming large and very luxuriant. There are several species of Cymbidium in nature, widespread in Africa, Asia and Australia; in the nursery, however, there are almost exclusively hybrid varieties, which therefore have very similar cultivation needs. They are plants that love a moist and fresh soil, for this reason the waterings must be supplied with great regularity, avoiding to leave the soil totally dry, especially in the hottest periods of the year. So in spring and summer the watering should be frequent, even daily in case of dry heat; in the other periods of the year watering can be reduced, especially if the pots are left in cool rooms, or outdoors with temperatures below 15 ° C. In these cases one can also water only once a week.
Grow the Cymbidium
The Cymbidium plants are among the simplest orchids to cultivate, because they can withstand even very high temperatures, above 30 ° C, as well as low ones, with nocturnal minimums close to 10 ° C. Respecting the alternation of the seasons is the key to making Cymbidium plants continue to bloom over the years. In fact, the flowers ripen in cool climates, with temperatures below 10-15 ° C; for this reason it is important to leave the plants outdoors at the beginning of autumn, moving them inside the house only when cold arrives, in October or November. In any case, as long as the floral buds are not well developed, it is advisable to keep the pots with the Cymbidiums in an area that is not too hot, for example in an unheated stairwell. The tufts of pseudobulbs can be divided, to give life to more plants; this operation is carried out after flowering, once every 3-4 years, to avoid overly disturbing the delicate root system. Care must be taken to create portions that contain a good amount of healthy and well-developed roots.
Fertilize the Cymbidium
Cymbidium plants are epiphytes, this means that in nature they do not develop in a soil rich in mineral salts, but extend their roots on rocks or tree branches, where they find only a few decomposing leaves, or other organic material. To stimulate a correct development of the plant it is good to cultivate it in a special soil suitable for orchids, completely incoherent, and containing pieces of sphagnum peat or coconut fiber, or even polystyrene. They do not need enormous amounts of fertilizer, even if it is good to fertilize regularly. Nitrogen-rich fertilizers are used in spring, with greater amounts of potassium from autumn until the beginning of flowering; these fertilizers can also be supplied once a week but must be dissolved in minimal doses in the irrigation water. Fertilizers specially designed for orchids generally have the correct dosage indicated on the label; if you prefer to use a generic fertilizer it is good to dissolve only 1 single cl per liter of water.
Pests and diseases
In nature the Cymbidiums live in cool and damp areas, slightly shaded; to best cultivate these plants it is good to try to replicate these conditions even in the apartment. They therefore prefer a semi-shaded position, with direct sunlight only during the coolest hours of the day. Care must be taken especially in summer, when the sun is warmer and can cause the total desiccation of the soil, which is particularly harmful to the plant's delicate roots. Parasites can occasionally attack Cymbidium, but proper cultivation care can keep insects and fungal parasites away. In the case of heavy soil, poorly drained and always soaked with water, the roots and pseudobulbs can be attacked by mold and rot. If grown in poorly ventilated or very dry situations the Cymbidium are quickly colonized by scale insects, which must be quickly eradicated using appropriate insecticides. If cultivated in low light conditions, with few waterings and few fertilizations, the Cymbidium will produce little foliage and look dull and not very luxuriant.