Jon,
An idea I've seen suggested for pest treatment on this listserv is to
immerse your plants in (rain) water for a day or two. Most pests will
either drown or leave. I have not had need to try this myself (knock on
wood) so I can't attest to the success rate but as we always say here in
the computer industry, "What could possibly go wrong?" :)
Seriously, if nothing else helps this might. Is is enviro-friendly, too.
Hope this helps,
Phil