You have to treat the soil too. Gently knock the plant out of it's pot. Two
to one you'll find masses of cottony young mealies. You'll know the
difference from the perlite in the mix. Look under the rim of the pot or
basket if there is one. Chances are you'll find some there too. This is one
reason they keep coming back on you. So besides spraying the top, mix up a
half bucket of insecticide and set the pot in it. Make sure there's enought
to reach the rim of the pot and leave it there until no more air bubbles
come up. Remove and let it drain.
Of course, take precautions to protect yourself. The minimum is latex
gloves. Also do this outside or in the garage to avoid the fumes.
I've heard of some people having success with just knocking the plant out of
its pot and spraying the rootball while spraying the top. And then repot in
a clean pot for a fresh start when things have dried off. Orthene is pretty
good since it also is a systemic so it lasts a good while.
Good Luck.
Gary

"Eric G" wrote in message
...
I have a mealybug problem with my houseplants and wonder if someone
can offer some suggestions on how to get rid of the pests?

These are the white mealybugs.
I had to throw out 5 or 6 large Diefenbachia plants because they were
so infested that it was hopeless.

I have a few other plants infected with the mealybug but it isn't out
of control yet and don't want to lose the plants.

Using hydrogen peroxide with cotton swabs just isn't practical. It
takes forever just to do one plant.

I bought an insecticidal soap and have been using the spray once a
week on the plants, but the mealybugs still keep coming back.

I read about using biological control (beneficial insects) and would
like to explore this avenue if possible. Is it practical for indoor
plants? How do you go about the process?

Where do you find ladybugs in the freezing snow and cold now here in
Canada? How do you release ladybugs so they stay on the plant in
question and not fly away somewhere else?

Thanks in advance! Eric