"David wrote in message
Update - it seems to be perking up a little - sign of some growth and the
roots have generally turned a healthy(?) green colour.

No, other than the growing tip the roots will only be green if damp,
otherwise they will be a light grey colour. If they are green all the time
then the plant is too wet.
It grows as an epiphyte, clinging to the branches of trees, so the roots get
wet when it rains but dry out quickly when the rain stops, especially the
ones that hang down from the branches and wave in the air. The fleshy leaves
are also storage organs BTW.


I understand the roots have to be exposed to sunlight to allow a
beneficial
fungus to grow, which is why the orchids come in clear pots.

And if growing well the roots will grow outside of the pot where they prefer
it, just don't let them get a grip on anything as you would have to break
them to release their grip..

However the growing medium includes a lot of sponge rubber(!) which will
presumably hold moisture well, but is the very devil to wet once it is
dry.

No again, it could be "Rockwool", anyway, some is made to be absorbant and
some is water repellant and remains full of air to ensure you don't
overwater and that those roots have plenty of air around them.

Trying the 'plunge then drain' method to see if this works O.K.

Excellent, but let the compost dry out almost totally before replunging it.
Never allow water to remain in the crown or on the leaves of the plant,
especially overnight. Most orchid growers water in the mornings for this
reason.

Is sponge rubber a normal addition to the growing medium, or is this a
mass
market 'budget' idea.

Rockwool and spong are a normal types of additions to growing media for
those orchids, it's inert and easier to deal with than the chipped
bark/sphagnum moss type compost although I prefer the latter in different
proportions for my plants.

--
Regards
Bob

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