My calamondin orange tree was a beautiful plant producing lots of oranges then this May fruit flies got into the soil. I kept it outside the whole summer. I Let the soil dry, tried the sticky pads, Schultz spray for fungus gnats, changed soil, put small rocks on top of soil because apparently they won't lay eggs in rock only soil. Now the leaves are dropping. I took it to a local greenhouse and the worker repotted it for me with a really good soil (he said mine was crap). When he did it the root ball was so small. He said that's why the leaves are dropping. The roots only took up half the pot when it should be the full pot. The pot is about a third the size of the plant. He told me to keep a clear bag over the plant for a few weeks too. These plants are impossible to buy where I am so u don't want it to die. Is there anything I can do to help it form more roots? After and before shots below.