I regretfully come posting asking for advice on how to get rid of a very tenacious spider mite infestation in one room of my indoor plants. I have become convinced these pests have become pesticide resistant because they have shrugged off neem oil, tobacco water, Sevin (Carbaryl), Malathion (a very strong organophosphate pesticide), Doktor Doom (pyrethrin, both the fogger and the spray), and something that came highly recommended called Wipeout.
Each attempt was whole-hearted, with me applying the pesticide at least 4 times liberally on the undersides of the leaves, spaced 3 days apart to get rid of the newly hatched eggs. Each time I see improvement for about a week before the leaves start getting sucked dry at an even more accelerated rate. I have also tried dusting with diatomaceous earth, and wiping down the affected leaves, all to no avail.
I am certain it is spider mites and not some nutritional deficiency because their webs are noticeable, I can see the wretched creatures when I inspect the leaves with a high powered magnifying glass, and its affecting multiple species of plant. Unfortunately heavy spraying with water is a non-viable option as the plants (mainly plumeria species) will suffer root rot if given too much water. I really do not want to have to discard these plants because they are fairly mature and rather unique varieties.
Is there anything on earth that will kill these vile pests without destroying my plumerias? As you can see I am willing to use just about any chemical at this point, but I am open to just about any suggestion. Your help is much appreciated.
[UPDATE] I tried both of Shule's suggestions of wiping down the leaves with rubbing alcohol and I spent some money on the predatory mites recommended. Rubbing alcohol didn't seem to damage the leaves terribly, and was very effective on the large broad leaves of the plumeria where it was fairly easy to wipe evenly. None of the leaves I wiped down suffered any additional damage. It was less effective on my ornamental peas where the small leaves made it difficult and tedious to wipe all the leaves. So I spent $60 on some Phytoseiulus persimilis mites. I hope they become established and permanently rid my plants of the irritating spider mites. I guess the moral of the story is don't use pesticides against spider mites. Thank you everyone for helping save my plants.