Well, the bonfire treatment will work, that's for sure! ;-)

Some plants can be sprayed with a rubbing alcohol and water mist. This allows for fast and thorough coverage into all of the nooks and crannies. Do some leaf tests before you attempt this. Mix one part alcohol to three parts water and apply it directly to a couple of leaves of each different kind of plant. Wait for three or four days to see if any problems arise. I can give you a long list of the indoor plants that this is safe to use on but not outdoor annuals and perennials.

Best to apply on a cloudy day, too. Avoid spraying on blooms.

BTW, rubbing alcohol is probably easier on the plant than a homemade soap spray!

If you want to go the chemical route, a systemic insecticide called imidicloprid works well against mealybugs, espesially when used as a preventative. I use it whenever I pot up a plant that I know is prone to mealybug infestation. It can be found in the products Marathon and Merit but is more easily found as Bayer Tree and Shrub insecticide. Good luck.

Many thanks to both of you for such helpful info. I tried the spray and it worked pretty well. As soon as I get to town am going to look for the insecticide. Do Home Depot or Lowes carry it?

Be sure that the label gives you directions regarding how to mix for container plants. The last I knew, Imidicloprid products did not list containers as a referenced use. If you have any questions about the uses of this and any other chemical pesticide, there is always a toll free number on the label.

I have seen Bayer Tree and Shrub insecticide at HD and Lowes, but Rhizo is right (as usual), it is only labeled for outdoor plants. You can buy Marathon 1% Granular online for about $125 for five pounds. A lot of money but it's probably a lifetime supply for most of us as it only takes about a half teaspoon sprinkled on the soil surface of a six inch pot to keep mealies, white flies, aphids, etc away for about three months.

I've used Sunspray UltraFine Pesticidal Oil on my fern and a few other houseplants that some mealybugs found tasty. The bonus is that this is actually an oily product and it left a beautiful sheen on my plants. I believe the oil is supposed to suffocate the bugs.

I plan to use this product again, even if I don't have bugs, just because of the resultant sheen.

To apply, I carried the affected plants outside in the shade. I mixed up a solution according to directions and applied generously to all plant surfaces using a pump garden sprayer. The plants were brought back inside when they were dry.

This was weeks ago. The plants did not suffer any ill effects (but the mealy bugs did!).