Hello, friend.
Here are some quick tips for cannabis pest control:
1. Spray Bottle-
You can clean your plants by spraying them gently with water. Make sure to get the undersides of the leaves too, as this is where many pests like to hang out.
2. Contamination-
Make sure to wash your hands and use gloves before tending to your plants. Wear clean clothes and avoid going in nature before going near your plant. Make sure to keep furry pets away, etc etc. you get the idea.
3. Air Flow-
Simply having a fan or two constantly pushing air over and around your plants can make it harder for things like gnats and flies to maneuver in your garden.
4. Organic Substances-
As you already know you can use things like neem oil to control garden pest. But make sure you are also applying it around the base of each plant as well as spraying the plant itself.
5. Trimming
Make sure to trim heavily effected and rotten leaves and remove them from your garden as to prevent spreading of said problem.
Side Note: (IMPORTANT)
When it comes to pest control the best coarse of action is directly based on the specific pest or disease effecting your plant. Pay attention to specific details about your problem and research what it could be before taking any critical action.
Anyways best of luck with your grow!!