Here’s what I did to situate my windowsill orchids for a 3-week
absence and how it worked out.

1. Bright-light plants (unobstructed southeast window supplemented by
   a 100 W LED due to KY latitude). This
   upstairs room gets hot in the summer, but I thought that in May it would be OK. Most of my plants are in “desiccators”
   (hydrators, in my case), which allows the plant to be mostly enclosed and down
   near the water in the bottom but open to
   the air at top. My bright-light plants
   here are a Maxillaria tenuifolia mounted on a slab and Diplocaulobium aratrifera in a net pot
   (raised just above water level). The
   plants first were watered thoroughly.
   The water-supplementation set-up for the 3-week period had 2 Water Worms
   secured with a staple in the pot or behind the mount, the other ends immersed
   in a jug of distilled water. The exposed
   parts of these wicks were wrapped with plastic wrap to prevent drying and allow
   them to be flexible. Large wet Telfa
   pads (white) dipped into the water at the bottom and adhered at the front and
   sides to provide humidity and reduce the light.
   These were clamped onto the edges of the desiccator with a couple of
   binder clamps to make sure they didn’t sag or fall. Plastic wrap was stretched across the top,
   but the plants’ leaves were still open to the room.

As it happened, outdoor temps were often in
the 80s, and the upstairs room probably got very warm. After 3 weeks there was still more than half
a jug of water, and the Water Worms were moist so the wicking system was
working. The Diplocaulobium’s status was
great: its medium was moist but not soggy, and the plant healthy (and I think
is starting to flower!). The Maxillaria was OK but clearly had drawn upon
its pseudobulbs, which now were somewhat wrinkled and creased instead of the
flat, sleek pbs of 3 weeks prior. I’m
sad about that and hope they will recover with TLC.

2. Shade-to-bright downstairs southeast window partially filtered by
   dogwood outside and an open-work curtain.
   This room’s temperature does not exceed around 78F. Here I have a Bulbophyllum masdevalliaceum in a net pot and a mounted
   Restrepia contorta. Same set-up as above
   with the addition of 2 small mayonnaise jars of water to add to the humidity
   for the Bulbo, which was left open to the air (left picture). The Restrepia was covered at the top with the
   plastic wrap. Result (right picture,
   plastic wrap removed): after 3 week the plants seemed to be in the same
   condition as I last saw them!

3. I confess I was chicken to leave my two small tanks of mounted
   minis and instead carried them with us to the beach house. One has shade-to-bright plants and one has
   shade plants; I suspect they would be OK mostly closed and stuffed with wet
   sponges and Telfa pads (which worked previously during a 10-day overseas trip),
   maybe with the addition of spice-jars full of water.