Answer: How sad! I know it's too late for you now, but it's always a good practice to isolate any new houseplant for a few weeks until you can assess its health. And, as an extra precaution, washing it with a strong stream of water is a good idea, as well. But, now that you've got an entire collection of plants with spider mites, you'll need to treat them all at once and repeat the treatments every 7-10 days for the next month or so. Start by spraying with an insecticide formulated for houseplants. Select one containing Neem oil, insecticidal soap or bifenthrin, and apply according to label directions. Most are contact poisons and do not have residual effects so I spray my plants, wait 10 minutes and then give them a shower with tepid water. This rinses away the dead (and not so dead) spider mites and also removes the spray from the foliage so it doesn't build up and clog the natural openings in the leaves. Be sure to follow label directions. Keep at it and you'll eventually control those pests.
Q&A Library Searching Tips