Hiya - I've got a small key lime in my sunroom and it produced tons of flowers all winter long. I tried to pollinate them with a qtip but that resulted in absolutely zero fruit set. I do the same thing (separate qtip) with my meyer lemon and got a great fruit set. What might I be doing wrong? It is flowering right now but has also lost a lot of leaves recently. I put Citrus Tone into the soil last fall when I potted it up.

My thought is that it isn't getting enough light or warmth. Key or Mexican lime is the most cold sensitive citrus species and they all require lots of light. Once you can put it back outside for the summer you'll probably get fruit.