My mother said: there's something wrong with my orchids, I give up on them, do you want them? These are Phalaenopsis orchids and I have some others that were successful rescue projects so I know that they are tough and apart from the massive infestation of wooly aphids, the plants weren't too unhealthy so I said "Sure!".
All plants become vulnerable to pests when they are subjected to environmental stress so although most orchid growers recommend getting rid of plants in this condition, on the grounds that the bugs are too difficult to get rid of, I think a thorough cleanup together with a change of growing conditions can be successful.
One pot even had an ant nest in it and although ants are notorious companions to aphids because they farm them - aphids secrete honeydew, which the ants crave, these ants were even incubating their pupae in the pot, which tells me that the pot is nice and warm and dry, not an ideal condition for phalaenopsis orchid roots.
The orchid in the ant-infested pot was quite pale but the other showed clear signs of sunburn. Phalaenopsis orchids do well in low-light conditions and should never be in direct sunlight.
So there were some very clear reasons for the them to be completely infested with aphids and it was time to get out the Mercaptothion spray, clean up the leaves, paying close attention to all the cracks and crevices
get rid of the potting medium, spray the roots, cutting off any dead roots
and repot in fresh bark chips. This is an bark orchid mix and although some people grow in sphagnum and other substrates, I use bark because it's the only growing medium that's easy to get here.
I'm feeling confident that I can beat this infestation because the plants are in pretty good condition besides the aphid infestation and I expect them to be more pest-resistant in a cooler environment without direct sunlight and more frequent watering. One plant has a flower stalk with active buds and the other is showing signs of new leaves
