Traditional Prevention and Treatment

• 1). Prevent hornworms by spraying young tomato plants with Bacillus thuringiensis, commonly known as Bt. Bt is a bacterium that produces proteins toxic to the digestive system of some insects, causing them to stop eating and die.
  
  
• 2). Kill existing hornworms by spraying tomato plants with a pesticide containing carbaryl, permethrin or spinosad.
  
  
• 3). Till soil surrounding tomato plant after harvest to destroy hornworm pupae.
  
  

Organic Treatment

• 1). Use tweezers to remove hornworms from tomato plants.
  
  
• 2). Put the hornworms in a glass jar and cover the jar with window screen. Place the glass jar next to your tomato plants. The hornworms will eject little white objects that are the cocoons of parasitic wasps. When the parasitic wasps emerge, they will kill the hornworms in the jar. The wasps will then fly through the screen and look for more hornworms.
  
  
• 3). Remove dead hornworms from the glass jar before adding new ones. At the end of the season, drown any remaining hornworms and dispose of them.