I've used Lady bugs myself. This was a method that I found to work very well.

Spray if you are going to spray the plants. Then wait 2 or 3 days and spray again. If you use a safer organic bug killer there might be some of the baddies left over because they aren't always as efficient as other products on the market. This is where the lady bugs come in. After I spray the second time, I usually wait another 24 to 48 hours... And then I release at least 15 to 20 lady bugs per plant.

Ideally you want these thing to survive as long as possible because the larvae eat more than the adults.

Good luck, happy growing! From here on out, hopefully no pests!