Hi Patti,

It sounds like your plants have the dreaded tomato pinworm. Luckily you are catching them early. A lot of times, people don't seem "them" until they've been in the fruit, left and all that's left behind is a fruit that is rotting from the inside out. Very rarely, an internal form of Blossom End Rot also causes black tissue inside a tomato, but since you are seeing the worms, we know it is tomato pinworm.

They usually hatch and are present on foliage first, though very tiny and hard to spot, and then tunnel into the fruit at the stem end. You can treat your plants by spraying the plants heavily---tops and bottoms of leaves, all stems and fruit, etc. with a caterpillar killer that contains Bacillus thuringiensis (Bt) kurstaki. Often these are listed as Caterpillar Killers on the label, or may be labeled as Thuricide, Dipel, etc. I think now that you know you have the pinworms on your plants, you'll have to spray Bt at 7-10 day intervals for the life of the plants.

The pinworms don't necessarily make it into each and every tomato on a plant, or even onto every tomato plant in a garden, so hopefuly they are not yet a widespread problem in your garden. I'd spray as soon as possible and be very vigilant about maintaining a regular spray schedule.

I've linked a photo of a tomato with severe pinworm damage, although your fruit may not have been as badly damaged. If you want to learn more about the pinworms, a Google search will bring up all kinds of info.

I'm sorry you have these in your fruit and I have found them to be fairly rare in my home garden. I'd guess I've seen them two or three times in the last 20 years, and each time it was just in the fruit of one plant, which is why speedy spraying helps----you can shut them down and keep them from spreading to the rest of the plants and fruit. The pinworms are much more common in greenhouse-raised tomatoes than in home gardens if that is any consolation, so even though you have them in your garden right now, that doesn't mean you're "doomed" to always have them.

Dawn

Here is a link that might be useful: Tomato Pinworm

Dawn,
Thanks for the answer. I was asking for my DD. They have trippled their garden space this spring and have put in over 120 tomato plants - I brought home several from the spring plant swap. They were just crushed when they found this one rotting this morning. With five children, ripe anything doesn't hang on the vines very long!! The tomato plant she found with the pinworms were from a green house in Guthrie, so as usual, your advice was right on!
I'm taking a day of vacation to work in my yard today. Went over to a pasture where they feed hay all winter and loaded my pickup with old hay/manure and then unloaded it around my Knockout roses and Thuji Green Giant trees. Uugh! I think I only covered about 10'. So with about 70' to go, I'm thinking the $4.50 straw hay bales at the Coop are looking easy.
Going over to DD tonight to help them plant 550 sweet potatoes. They too live out in the country and have worked up their front yard and made raised beds. They have marked the rows with dibbits for 550 plants. My job tonight will be to water each plant with one cup of miracle grow after it's planted. They have five children and eat virtually vegetarian. Last year they planted about 300 plants and had sweet potatoes till March. So they have increased the amount and hope for a good crop. They wanted three spaces large enough to plant this amount of sweet potatoes so they could rotate them. Our poor SIL is a 2nd grade teacher teaching summer school and has been out digging and tilling at 6:30 am, teaching school from 8-5:30 and back out till 9:00 pm - all with a torn ACL. I call that dedication!
Thanks again for your help. You're a walking garden encyclopedia!!!
Patti

Patti,

You're welcome.

It sure was a hot day to be out gathering all that hay and manure, but just think how gorgeous your roses will look, and that will be your reward for all that work.

Wow! What a large garden DD's family has this year.

I hope the pinworms are not widespread and I do think you caught them early since you found them while they were so small. The good thing about Porter is that each plant pumps out heavy loads of tomatoes all summer long! Just thinking about that tomato variety takes me back to long ago when Gene Porter was still alive and you could buy your Porter seeds (and others) from the now-defunct Porter & Sons Seed Co. in Texas. He and the company have been gone for some time now, but at least their tomato lives on.

That is a dedicated SIL, working out in this weather with a torn ACL and all while teaching summer school!

I hope they have a bountiful harvest and I am sure that they will.

Dawn