I have had GREAT success using mosquito dunks. I get them at Agway or Blueseal, but they probably have them any home improvement or livestock supply place. They look like little donuts of gray grit. I break up a donut, stick a piece in my watering can, let it sit overnight to dissolve a little, then water as usual. And after a couple of weeks, the gnats are completely gone. The piece stays in the watering can and I just forget about it. Can't tell you how many times I've saved a hibiscus with this. It's what people use in horse watering troughs, bird baths and fish ponds to kill off mosquitos without harming the animals. Of course, since joining this forum, I've learned the problem is poor soil and overwatering, but in the meanwhile, there's the dunks to help out. lol From wikipedia on Mosquito dunks: "Bacillus thuringiensis serovar israelensis (Bti) is a group of bacteria used as biological control agents for larvae stages of certain Dipterans. Bti produces toxins which are effective in killing various species of mosquitoes, fungus gnats, and blackflies, while having almost no effect on other organisms. Indeed this is one of the major advantages of B. thuringiensis products in general is that they are thought to affect few non-target species."

I did not see where you stated your garden is. Since it is in zone 5 perhaps this article may be of use. http://www.pghrosesociety.org/rosemidge.html " So far researchers have not been able to come up with a good biological control for rose midge. The only scientific study published in the horticultural literature on in subject of rose midge control appeared in 2006 authored by Dr. Janice Elmhirst, director of the Elmhirst Diagnostics & Research Corp. and was performed in selected test gardens located in British Columbia, Canada. This study compared two biological agents, two live predator insects, a chemical control, and an untreated control plot. The two biologicals tested are commercially available, one being AVID (with the active ingredient abamectin derived from the soil microorganism Streptomyces avermitilis and the other DOKTOR DOOMî, a ready to use permethrin formulation. The predators were a nematode (Steinernema feltiae) and a predatory mite in the form of an unidentified Hypoaspis species. The chemical control was Matador (lambdacyhalothrin), which is similar to the active ingredient in the Bayer chemical products mentioned earlier. The results of this study were interesting in that the predatory insect approach actually had a higher level of midge damage than the untreated controls. The best result came from the Doktor Doom product with less than 2% damaged rose growth. The next best was the chemical control with approximately 4% damaged tips. The Avid did better than the control but not by a significant amount." Here is a link that might be useful: link for above

I mostly agree with the previous response, but have some extra thoughts and a few points where i differ a little, take these for what they are worth: In container plant culture, conventional wisdom is not to "pot up" too drastically. In other words don't take a plant in a small pot and put in a very large pot. However, it sort of depends on how vigorous the plant is. In my zone, tropical hibs grow fast and I wouldnt think twice about putting your hibiscus in 12 or 14 inch clay pot. But I really don't do these fancy sinensis hybirds and have heard that they are a little slower. My guess is that it won't matter, provided you use a well drained container medium. I say use your biggest clay pot, just use a good soiless mix. The reccomedation to use a product containing imidacloprid is correct, but not a spray application. What are you going to spray? You don't have bugs yet! Dont use it on the tomatoes if you want to eat them! Use the systemic version and water in. Also by bayer. I do disagree with the advice not to use a clay pot. They drain and aerate better than plastic, especially if not high fired glazed pots. If you say the plant doesn't like 'wet feet', then a clay pot is probably better. Also looks much nicer. As for when to repot, summer is ok with these, but if you just got it, I would not disturb the root system too much, you could kill it. Just break it up a little, cut away some circling roots. Save the major repot for later, after you know it's established. The previous poster is correct in saying that the plant can in theory be kept in a container indefinitely, provided you know how to take care of it. Bonsai enthusiasts grow redwood trees in containers smaller than your 14 inch clay pot, it just takes some work. Im not checking the link, mine "over winter" inside only for a day or two at a time because freezing temps are realtively uncommon. However, I do grow plants indoors and would say that even a sunny window is unlikely to provide a sufficient amount of light to keep the plant happy for too long. And a plant weakened in this fashion is extra susceptile to insects like white fly. Some artificial light will help a lot, but thats another discussion........I say go all out and get a 1000W HID, you can grow tomatoes inside in the winter To recap my suggestion: put that thing in your biggest clay pot, dont disturb the roots too much yet. Use a good container mix. Not just off the shelf miracle grow potting, add some extra drainage material (perlite is fine for this). Water in a systemic containing imidacloprid and buy a grow light big enough to make the neighbors wonder if you're growing weed. Good luck. Hope it works. let us know.

What is the soil mixture..and there is always hope..your hibiscus might just be presently in a dormant state due to shock,..Id make real sure your soil mix is good...perlite and moss for good drainage yet some moisture retention..there are also other soils that say they have a soil that retains moisture without basically remaining soaked..mixed with perlite and moss a good amt and a bit of mild food boost to it and then sun lots of sun...sit and be patient..trim back as u didnt say how much branch length there is but a trim may also help build strength to the plant ...remember a plant is only as strong and healthy as ITS ROOTS..so many forget this..even if bugs infest a plant ..if the roots are strong and healthy it will come back..good luck its worth the extra patience and better soil.