Tobacco budworm is resistant to most garden insecticides. In addition, using them may kill beneficial insects such as wasps, bigeye bug, damsel bugs, minute pirate bugs, and spiders. If you use an insecticide, look for one with synthetic pyrethrins also known as pyrethoid insecticides.he budworm is a real threat to tobacco crops, too; fortunately for tobacco farmers they have more potent pesticides and better training in using them than the ordinary gardener. I discovered these worms (also known as the geranium/petunia budworm) last summer in my petunias.