Aphids

Yesterday I discovered some aphids indoors on one of my flowering annual plants that had been outdoors during the summer. I'm not sure if it's had the bugs since then or if the extra soil I put in the pot recently had the bugs inside. At any rate, I don't think any of the other houseplants have aphids. In order to kill the bugs, I put the plant outside in the freezing cold for about two hours. I also sprayed the leaves with soapy water. After this, I trimmed all the plant parts that had infestation. I think I've destroyed all the bugs. Since being brought back inside, the plant hasn't been fairing that well. Obviously it has some frost damage even though it wasn't outside too terribly long. There are still a few leaves that are healthy near the bottom of the plant so I think it will live.