I use a solution of one quart water, one teaspoon dishwashing liquid, and one teaspoon cooking oil. This is pretty much as effective as anything you'd buy in the store, and cheaper. It kills pretty much all soft-bodied insects. I'd maybe do it once right before bringing them in, and then once a week for a couple of weeks. Make sure you spray the underside of the leaves as many pests prefer to hide there.

Another thing I recommend is getting some of those colored rocks that they sell for aquariums and covering the top of the soil with them. This serves as a "mulch" to keep water from evaporating and keeps certain insects from laying eggs in the soil. Plus, it's kind of attractive.

Danny, last Fri, they predicted temps would drop in the 30's..
What I did was start w/tender tropicals/perrenials,& C&S. I carry one plant in at a time..take directly to sink. Hose and rehose..You wouldn't believe the number of earwigs I drowned..Yuck.
The remaining outside plants are mostly trees, therefore I can't take to kitchen sink..these will be hosed down outside..after they're allowed to air dry, I spray w/Fish Emulsion, dish soap, crushed garlic and citrus rind. I made sure I had rind available just for this purpose..A little rubbing alcohol might benefit too, but so far, cross my fingers, plants haven't had mealy..The two insects I worry about are scale and mites..FE rids scale, and the other 3 ingredients should take care of the mites..I hope..LOL.
It's supposed to heat up again this wk, which will give me time to clean out my little gh..This way, when it's time to bring in for good, they'll have a nice, clean, warm place this winter..
Another thing, pick out a spot in the house where plant will overwinter. Clean the area, make room. This way, after you clean off plant/s, you'll be a step ahead of the game.
Good luck..Toni

I had to start bringing some of mine in at night several weeks earlier than I wanted to - four baby raccoons discovered all these interesting things on the porch and started knocking things over one night. I brought in all the hanging ones last night because they were saying possible frost. I'll put the Christmas cacti and the jasmine back out this week - it's supposed to warm up some - but the others I'm going to start acclimating to indoors again.

Luckily there were no mealies or other nasties on anything other than my piggyback plant, although I did have to pull sunflowers out of a number of pots - that's what I get for having a busy birdfeeder on the porch too. :) My monstera is not happy about coming in, though - it's been "weeping" for three days now. (Can't say I blame the poor thing. I hate seeing winter coming, too.)

I brought in about 20 houseplants last Saturday as it was cold and rainy and I just had a feeling I better get them in before it got too cold... it has been in the 60's at night so far, I was wrong but I say better safe then sorry, of course then I had a TON of rearranging I had to do with all these plants in the middle of the living room.
All I do every year is spray every plant down with a garden house before bringing them in, so far 5 years later I have had no unwanted critters in my house, the only thing I have the problem with is frogs.. I always do my transplanting in the middle of Winter when I can't do any outdoor gardening, and I always find frogs hibernating in the pots, that is the main reason I don't use any pesticides, I am afraid of hurting them if they are in there.
My Monstera was one of the plants I brought in, I stuck him in my bathroom, so far he seems okay, I worry about that one.

Thanks, everyone for the great advice! I love the natural insecticide suggestions. Micke, thanks for mentioning the frogs! I have a whiskey barrel pond in front of my porch and tons of frogs have taken up residence there. It's been fun watching them all summer. I sure wouldn't want to hurt them by spraying anything toxic near them. I guess I'd better get busy finding room for these plants that have doubled or tripled in size over the summer. I'm just recovering from a bad back problem, so I have to take it slow and be careful. Hopefully I'll get em all in before it gets too cold.

Thanks again!