Watering and Humidity
In general orchids have a growth period (beginning and active), a rest period and a blooming period. The beginning of the growth period is characterized by when the orchid starts to produce new shoots and roots and it is followed by the active growth period as these new shoots and roots develop into leaves and pseudobulbs. During this active growth period the plants need to be not only watered often but also have a high humidity environment. When the plant's growth begins to slow down the orchid starts the rest period and its needs for water and a humid environment decreases.
After the rest period, the orchid is mature and will flower or not depending upon the conditions under which it has been cultivated. The frequency of watering is one of the most difficult and delicate operations to master in the cultivation of orchids. Each genus and sometimes each species has its particular needs but in general, after allowing the container compost to dry out before any watering, one should water in abundance until the water flows freely out the container drain holes.
Although this rule is not ideal for every species of orchid, it can be taken as a basic rule because it is easier to kill orchids because of too much water than too little. The species of Cattleya, the most popular orchids, need this kind of watering. On the other hand, however, micro-orchids, the species of the genus Phalaenopsis, Miltoniopsis and terrestrial orchids like Cymbidium and Paphiopedilum require the compost to be always moist but not soggy. How long the compost will take to dry out is determined by the following factors: