Hi, I live in Baltimore and have pretty much the same forecast as you. It was predicted to be in the low 40s last night as well, so I brought in all except my christmas cacti and amaryllis yesterday. I am not suggesting what to use, so take this for it is worth to you.:) I always use Neem oil, according to package directions, as a preventative while my plants are summering outdoors. If I see a mealie or some other pest, I'll also use a spray of undiluted alcohol to kill those that I can see. If it's even a light infestation, I use a systemic insecticide, but only outdoors and with proper precautions. BATS(Bayer Advanced Tree and Shrub)is my preferred brand. My plants have never had any ill effects from using any of these products. I use Ivory dishsoap with my Neem oil, 1 tsp or slightly less, per gallon of water. Whatever you decide to use, just be sure that you don't allow your plants to sit in the sun after you spray. Your plants will burn if you allow this to happen. It's a lot of work trying to get plants debugged before the winter migration. Next year, start debugging at least one month prior to this time. This way, you'll have enough time to eradicate or at least gain control of any insect populations. Oh yes, and I do leave my christmas cacti out until the first frost.

I just wanted to add my own experiences to the mix. I have been taking houseplants and a couple of tropicals out for the summer and back in for the winter for about the last 6 years. I am an organic gardener and don't use pesticides. Once I read an article suggesting you could just put a drop of water in a spray bottle with some strained garlic and water and spray with that. That worked fine but I really didn't have any visible insects or disease going on, it was just as a precaution. I've used that same spray in the past when I did have something eating the leaves and wasn't sure what. The last few years, I've done nothing more than spray the plants very carefully, with just water, careful to include the underside of the leaves, with as strong a spray as the plant will tolerate, inspect it very well, and remove the top couple of inches of soil and replace it before bringing in. Last winter I don't remember seeing any bugs at all in the house. This year, I did notice one spider that isn't a type that I normally see in the house and I don't know if he hitched a ride in one of the plants. That was it. In the garden this year, I had initial outbreaks of aphids on roses but I quickly saw ladybugs show up and barely saw another aphid the rest of the season. I did have a few Asian beetles that gave me a headache and I tried to keep the numbers down, by going out after dark and flicking them into a cup of soapy water. That worked out fairly well. I did have some foliage damage, but nothing I couldn't live with. I had earwigs a few years. I mulch a lot, and I think I read they are attracted to mulch. I kept up with them with a cup of soapy water after dark too. This year, I had more caterpillars than I've seen before. The little tiny green ones on roses and hardy hibiscus, and I just hand picked those off. Interestingly, I had a Carolina Wren in the garden this year. I read that they eat mostly bugs. He was a cute little thing with a pretty song and some funny ways. In the spring, we have had an infestation of winter moth caterpillars on the Maple trees for four years now. The last two years, a flock of Starlings have shown up and I can see them hopping in the canopy eating the caterpillars. I think I have a gourmet buffet of food for birds out there. [g] I seem to manage to just let it all work itself out. I'm surprised that I can do the same thing with the indoor plants, but it does seem to work out just using mechanical techniques rather than chemicals.

What you are seeing is probably fungus gnat larvae. Placing a mosquito dunk in your watering can will get rid of them. I've also heard placing bay leaves in the containers works. Spidermites like sundews and pings so keep them away from where the MG was.

Any tropicals will be fine when nighttime temps stay above 55° at night.