Good suggestions from Kathy. You really do need to determine what sort of
Dendrobiums you have. I would suggest that light might be your problem.
You state that the light they are receiving is less than optimal. From my
experience in Australia, most like a lot of indirect light. Depending on the
type of Dendrobiums you have and their parentage some can also tolerate a
lot of direct sun light short of burning. e.g D. kingianum and hybrids. Our
problem here is often too much light - yours might be too little. What
colour are the leaves? If very green they are probably not getting enough
light.

John

"K Barrett" wrote in message
. ..
Both you and your friend are right. Dendrobiums are a huge diverse group,
some of which like to go totally dry for long periods of time, others like
to be kept moist like other orchids. So you need to figure out which sort
of dendrobium you have. If you are in the USA a decent book is Ortho's
'All About Growing Orchids' (sells for about $12 or see if the library has
one). Their abbvreviated overview of the various types of orchids would be
a decent beginning. Their dendrobium pages at least would tell you what
general type of dendrobium you have. Then you can make an informed
decision as to how to proceed.

K Barrett

"C. Berlin" wrote in message
news:VFwTi.3800$uE4.371@trnddc07...
I have a few dozen orchids, mostly no-name, growing in my window sills (on
porch in summer). I've been able to sucessfully get the phals, paphs,
cymbidiums, oncidiums, and masdevalias to all bloom nicely over the past
few years. However, no luck with the dendrobiums. I have two that look
very healthy (lots of growth) that I've had for ?3-4 years, but have never
rebloomed since I originally got them (can't remember where they came
from, and no labels). I've read that many dendrobiums need a dry period,
and one acquaintance who does well with orchids says to let them go
totally dry for a long time, and lose all their leaves, then begin to
rewater, and they'll then bloom. But I've also read that there are some
dendrobiums that should stay watered and green year round. I'm thus
confused what to do here, and I'm a little uneasy about letting them go
totally dry for a long time. What I've actually done is somewhere in
between, just very lightly and infrequently watering in the winter. While
the plants stay healthy, no blooms. The light I have through the windows
(west facing glass patio doors) is less than optimal. They get the same
very dilute fertilizer as everything else does.
Any advice about what to do to get these to bloom will be appreciated.
Chuck B.