Since you are planning to grow under the lamps 12 months - I would
change the bulbs 1 every 6 months.. Or at least a month a part as you
have started them at the same time. Sometimes the change of all the
bulbs at once is a SHOCK and sometimes they are so secondary that it
is no more different than the change in day length. I am assuming
they are the major light for this group of plants.

Your Den's probably need a dry rest in the fall and winter months to
initiate bloom.
SuEhttp://orchids.legolas.org/gallery/main.php - Hide quoted text -

- Show quoted text -

Hi Sue and thanks ... the lights are meant to supplement natural
lighting, and enhance it.
You mentioned "...Den's probably need a dry rest in the fall and
winter months to
initiate bloom." I thought Dendrochilum's didn't rest, but grew all
year?
Bob