Here is how I use Neem oil. It is an easy regimen to follow but it is 110% effective.
Neem oil is not only a smothering control on insects but it is systemic as well. It does not kill everything on contact.
You are dealing with thrips, aphids, mealybugs or whatever you have. I use a gallon pump sprayer. I fill it with water, add 2 teaspoons of Neem and 2-3 drops of dish soap, not dish detergent.
Spray the entire plant 100%. Every part. Up, down, over and under. If you are having problems this is likely why. Your coverage is not 100 percent. Spray say on a Saturday, not in the sunlight!! 10 days to two weeks later, spray again. Ten days to two weeks later, spray a third time.
The first application smothers the adults. The second application kills off the young that have hatched from eggs since the first spray that you did. The third spray is one for good measure! One to make sure you smothered all of those little creeps!!!
Now spray again, but just once, a month later but make sure that you always hit every nook and cranny with the spray otherwise the population will just explode again!
Continue to spray only once a month, say the first Saturday. Whatever is good for you. In the meantime, your plants will take up the Neem internally through the roots. You'll gain a lot of residual protection. Once you are 6 months into this 'program', you can even skip a month. The systemic nature of Neem affords you protection. No sweat, no problems, easy peasy!!!!
Good luck!
