Ray wrote:

2) I don't think "humidity trays" are of any real benefit.


I agree, although they do a good job of keeping excess water off the
windowsill (or carpet). A little gravel in the bottom is good in order
to lift the bottom of the pot above the water surface, or I usually use
'egg-crate' lighting fixture covers (you can buy them at the home center
in the lighting department - 2x4' sheets).

If you want to 'build your own' humidity tray, you can easily make
them as long as you don't want them to be portable. Tools: hammer,
handsaw, and staple gun. Materials: lumber, a few nails, staples, and a
sheet of heavy plastic. I used 2x4 lumber to build a 'box' of the size
I wanted, and lined that with the heavy plastic. Staples (on the
outside of the box!) hold the plastic in place. If the whole thing
isn't sitting on a flat surface, you want to put a plywood bottom on the
box. My trays were 4' x 8' long, and cost perhaps three dollars to
build... At that size, they probably do a reasonable job of
humidifying, although just grouping enough plants together in a small
space will greatly increase the local humidity.

You can drain the water out of the trays (if it gets too deep)
with a siphon, or maybe a wet-dry vac. If you can drill a hole, you
could put a drain tap on the bottom (you can get a plastic valve at a
home-brewing store, if nowhere else).

With the appropriate frame and a little bracing, you can make a
light cart out of these 'trays' as well. I've seen them four levels
high. No advanced engineering degree is necessary, but you might want
to add more support than you think is strictly necessary (water is heavy).

--
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2) There is always room for two more orchids
2a. See rule 1
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