Alternative Pesticides Several alternative pesticides might be suggested for controlling thrips. Being contact pesticides, however, their effectiveness in onions would probably be limited. In contrast, three applications of superfine sulfur are recommended at monthly intervals in fruit crops for spring thrips control. The agent is a fungus that grows and reproduces in the host, therefore, effective control may not be observed until 7-10 days after application. Furthermore, neem has proven less friendly to beneficial insects than once believed.
Solids are strained out and enough water is added to make one gallon of concentrate.
Note also that several natural pesticides may be unacceptable or limited in certified organic production. Growers are advised to check with their certifying agent before purchasing or using any such products. While a potential problem in many vegetable and flower crops, thrips can be managed through an integrated approach involving cultural techniques, genetic resistance, biological control, and the use of environmentally benign pesticides. Coviello, R., S. Orloff, W.J. Bentley, and W.E. Chaney. Onion and Garlic Pest Management Guidelines.