AM very fond of moth orchids and have bought several plants. But
after flowering I don't have much luck - the leaves turn yellow
and die off.
orchids (Phalaenopsis) are from the tropics, so they need
more critical care than the relatively easy-care cymbidium orchids
that we can grow outdoors in many areas. Temperature and water are
the most important factors. To grow well they need a minimum of
16-18°C, but ideally 20-25°C. If it gets too cold you'll get slow
growth or no growth, leaf yellowing, possible leaf spotting and,
in extreme cases, leaf drop. Similarly, too much water, especially
if the temperature is cold, will cause root rot and leaf drop.
It sounds like you may
be overwatering your plants. Also, you must not leave them standing
with their roots in water for too long.
Although all this may
sound difficult, it isn't really. Moth orchids make good indoor
plants in a well-lit room and will stand the odd cool temperature
as low as 10-12°C, as long as you keep them on the dry side at those
times. And they'll generally flower each year with spikes of longlasting
blooms. Feed every couple of weeks during summer with a general
liquid fertiliser. For more detailed information, check out www.rnzih.org.nz/pages/Moth-orchids.htm
Gardener, Issue 204, 2006, Page 38
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.