I have had problems with tomato hornworms for the past two years. Do think it would be beneficial to spread Beneficial Nematodes that can be purchased from a supplier on my tomato beds this spring prior to planting tomato plants?
Hi. How large a crop of tomatoes do you grow? If might affect the type of control. I was unable to find any scientic data from a university that deals with your question. That usually means no research has been done on a topic. Bt is a spray that can be used but it also kills beneficial insects. The pupae from the hornworm overwinter in the soil so it could also be beneficial to rotate your crop. There are beneficials that are attracted to hornworm-notably a parasitic wasp. Also, looking for eggs on the underside of leaves and hand picking hornworms are tried and true methods.