View Single Post
  #4   Report Post  
Old 17-09-2006, 05:44 PM posted to rec.gardens.orchids
Nancy G. Nancy G. is offline
external usenet poster
 
First recorded activity by GardenBanter: Jul 2006
Posts: 85
Default black specs on Oncidium


I looked this morning and there were a few more black specs. I watched
them and at first nothing moved, then suddenly one seemed to jump off.

They are only on the unopened buds. Nothing on the flowers.

I checked my Phal and it's fine, at least the leaves look fine. There
are no flowers or buds on it.

So I guess I need to treat it with something. I have an excellent
local nursery. I'm sure they can help me.

As for the pot - I rechecked and there is a plastic liner in the clay.
I will be very careful not to over water. My Phal is in something that
feels like peat moss. It's easier to test for moisture than the hay
like stuff the Oncidium is in.


The coarser mix for oncidiums is OK. It should contain more stems, be
packed with the stems more vertical instead of around the pot, and
looser than for the phal. Most oncidiums develop pseudobulbs (the
smooth bulge between the leaf and base of the plant) to regulate water
uptake to the leaf. They need extra drainage and air around their
roots to prevent rot. You may be able to water on more or less the
same schedule as the phal, just make sure that the onc. drains
thoroughly and does not sit in water.

One more question: My Phal - I cut the flower spikes down a bit but
not much. Should I cut them all the way down?


Some phals will start new growth at the nodes on the spike if the spike
is still green and live. These may be new plants (keikeis) or smaller
bloom spikes. When I don't know the habit of the plant, I will cut the
spike down and leave 2 or 3 nodes, usually about half the of the
original spike. That helps to keep the height manageable if it does
branch and bloom from there.

This is the best time of year to provide for the necessary temperature
drop to initiate blooms. Of course, I'm assuming now. Some phals will
bloom in the later summer, but most of the commercially available ones,
naturally bloom in the late winter / early spring, It's tricky to tell
because they "force" the plants to bloom year round. In your case I
would recommend aiming for a 15 to 20 F drop in temperature (70's
during the day, 50's at night) to stimulate the spike process. The new
spike may be confused with a new root for a while. The spike will have
a more square shape than the root, and naturally as it develops will
stay green and grow towards the light.

Happy growing,

Nancy