The flower parts start to develop once the plant is sufficiently mature and external conditions are right. Floral initiation is regulated by a combination of complex exterior conditions specific to the native setting of each orchid species.
Some species need a dry period, while others react to day length or seasonal variations in temperature and humidity levels. Growers attempt to recreate these native conditions by adjusting the factors that influence growth and flowering.
It is best to water in the morning with tepid, non-chlorinated water. Allow the water to stand for 24 hours so that the chlorine can evaporate. The leaves and any roots growing outside the pot can also be lightly misted.
Watering frequency needs to be adapted to the different orchid genera, to the plant’s stage of development (plantlet or mature plant), the season (rest, growth, flowering) and the growing conditions (medium, light, temperature and relative humidity).
Sympodial orchids with pseudobulbs (Cattleya, Cymbidium) are adapted to daily and seasonal cycles of humidity and drought in the wild. The potting medium must be allowed to dry out completely between waterings year-round. They must be given good relative humidity, however. Water them more frequently in summer. Orchids grown on mounts may require up to twice-daily watering.
Monopodial orchids without pseudobulbs require regular watering year-round. The potting medium for Phalaenopsis and Paphiopedilums must be allowed to dry out to a depth of one-half between waterings. For Vandas, wait until the medium is completely dry, but keep the relative humidity high around the plant. During the growth period, mist the leaves frequently or install a humidifier.