holes in tomato fruit

Asked July 24, 2017, 7:47 AM EDT

Some of my tomatoes have holes eaten in them, as shown in the picture. The plants are covered with wildlife netting or barrier fencing to keep out deer and bunnies. Inside the holes, the fruit gets black and rotten. I found three tomato hornworms, but they were covered with white eggs, and I found that those were from a parasitic wasp, so I didn't kill them. Could hornworms be eating the fruit? The stems and leaves are not eaten.

Charles County Maryland

3 Responses

Very cool to see the cocoons with the tops chewed open. That means the little wasps that parasitized the hornworm are out continuing their lifecycle.

The round, dry holes are probably caused by another caterpillar, perhaps a climbing cutworm, armyworm, or even a tomato fruitworm that failed to continue his journey to the fruit center. Caterpillars will often feed a bit and then back out, leaving the fruit vulnerable to secondary pathogens.

Tomato/tobacco hornworms gouge green fruits.

I have an organic insecticide with spinosad. Is that effective against these caterpillars?

Also, I saw this small flying insect land on a tomato leaf. The picture is a lite blurry I know, but it was about 1/3" long and colored an iridescent blue-green on the front half and black on the bottom half. I left it alone as I didn't knowi f it were beneficial. Can you identify it?

Spinosad is effective against caterpillars. The caterpillars that produced the dry holes are long gone. Insecticides should only be applied when the pest has been identified and the level of injury warrants a pesticide application.

Appears to be a type of green bottle fly or blow fly. Completely harmless to veggie plants.