CNG encourages mechanical and cultural methods as the first line of defense against weeds, pests, and diseases. When those methods don’t solve the issue, most botanical and biological controls, such as ladybugs, BT, neem, or kayolin clay, are also allowed. (Rotenone is a notable exception; though it is an unprocessed botanical, it has been linked to Parkinson’s Disease). As a general rule, most OMRI-approved products meet CNG standards. No synthetic herbicides, pesticides, or fungicides are allowed.