And some work as both contact and stomach poisons. The following are some of the insecticides and miticides commonly used on vegetables. These are natural insecticides derived from plants. They kill a broad range of pests. Pyrethrin acts quickly on contact, paralyzing insects.
Rotenone acts more slowly and works as both a contact and stomach poison.
Both break down rapidly in light. They can be sprayed one day and the vegetables harvested the next day, making them the most useful insecticides for vegetables that are picked frequently. Because they break down rapidly and leave little residual, they must be applied more frequently. Pyrethrin is contained in Ortho Tomato Vegetable Spray and Dexol Vegetable Garden Insect Spray. Rotenone is contained in Ortho Rotenone Dust and Spray and Acme Garden Guard.