Date: 28/12/2009

It is a common mistake tof assume that orchids are native to tropical rainforests and they should be watered very frequently. Unfortunately overwatering kills the plants more frequently than under watering. Superficially over-watering and under-watering look alike. Leaves gets wrinkled in both the cases.

If in doubt examine the roots

a) Over-watered roots look brown and mushy
d) Under-watered roots look pale grey and dry

Orchids with pseudobulbs (thickened stem for water storage) like Cattleyas and Oncidium could be allowed to dry before watering. Vandae needs daily watering due to the lack of water storage. Hence Vandae, Ascocenda and Phalaenopsis should be watered just before full dryness probably daily in summer months.

Photo: The use of mist for watering helps to counter dry/less humid temperatures

There is no one rule that works for orchids. Watering needs depends on the humidity, temperature, potting media etc. Hence palnts needs to be checked for signs of dryness like appearance, weight and if needed stick your finger in the medium! The primary water requireents can be divided as follows:

Orchids to be kept evenly moist (not soggy or wet) at all times: Paphiopedilum, Miltonia, Cymbidium, Odontoglossum

Orchids to be kept evenly moist during active growth: Cattleya, Oncidium, Brassia, Dendrobium (Could be allowed to dry when not in an active growth phase)

Orchids to be kept nearly dry between waterings: Phalaenopsis, Vanda, Ascocenda.

In a family of plants as large as Orchidaceae, there are, of course, exceptions to these rules. Always be sure to ask for watering instructions when you purchase a variety of orchid with which you are unfamiliar.