Hi! I've been treating a peace lily and a sword fern for spider mites for several months... I initially was using neem concentrate, but to no avail... I finally took the plunge and bought Bayer Insect and Mite killer (recommended by the local nursery). I have a half gallon pump sprayer, which I added about three tablespoons of the concentrate to, then added water (the bottle says 5 1/4 tablespoons a gallon). I sprayed last weekend quite thoroughly and was definitely expecting results... I went to water them and return them to their proper homes today, to find that the mites are booming in population! What??? I then took the sprayer (now about a third full), added three more tbl spoons plus water and gave it another shot... Are you kidding me??? They didn't even react to me spraying, no, soaking the soil down. They started running again as soon as it soaked in. HELP! This is ridiculous.

Great Forum!

Spider mites are tough to get rid of...I lost a couple of plants to the red variety because only chemical methods were available. They're very hardy and may be resistant to the chemicals you're using. How about trying biological control? I believe that there is a species of predatory mite, available at some garden shops (and possibly online) that eats them, and then dies when they're gone. I read a few things saying that ladybugs may also work but I'm not sure. If you don't want to try biological control, then you can also see if there are any other chemicals approved for mites to which yours are not resistant.