It is sunscald... not from the heat, but rather from the fruit getting too much direct sunlight. It is actually a fairly bad case of it, as most of the time I see the scalded part to be the size of a quarter or half dollar. Are you pruning the foliage any?

Posted the same time as Dave...

I haven't done any heavy pruning up to this point. My plants are still growing so there hasn't been a whole lot to prune. How can I prevent scalding without blocking out necessary sunlight?

Should I cut the damaged fruit off the vine & try to save the rest that are still healthy?

<How can I prevent scalding without blocking out necessary sunlight?>

Plant in a diff location? That doesn't receive as much direct sun. Or plant at a diff time of the season.

<Should I cut the damaged fruit off the vine & try to save the rest that are still healthy?>

I would. Compost them?

> Should I cut the damaged fruit off the vine & try to save the rest that are still healthy?

if you aren't going to eat it, then no point having it around, and you definitely want to remove them before they start rotting.

depending on how many plants you have, you can cover the fruit exposed to the most sun by using some type of light-colored breathable bag or a roll of garden blanket which you can cut to size and rubber band around the fruit

I'd remove them and pitch them since they will rot anyway so nothing gained by leaving them on the plant unless they are acting as shade for ones below.

If you aren't pruning are you sure your plants got enough nitrogen for full growth and leaf development? Like GB asked, is this when you would normally have tomato plants going? I'd think in 9b, since you can plant so early, the plants would be about done with tomatoes until Fall.

Otherwise, yeah about all you can do is rig up some light shade for protection from the worst of the sun exposure but that can create problems of a different kind.

Dave

Like mentioned, by the time there are fruits on the vine, there should also naturally be enough foliage to prevent sun scald for the most part. Heck, I prune to 3 stems and rarely see sun scald and it is pretty sunny here in Charlotte, NC.

Sunscalded tomatoes generally don't rot. That is a pretty bad case of sunscald though, like half the tomato is affected, not much point keeping them probably.

Sunscald is partly due to sun, and partly due to heat, it's not just the sun. I see a black fence near the tomatoes? That will raise the temperature a lot around the plants. Not much one can do except cover the fruits as has been suggested, or a shade cloth over the plants.

"Sunscalded tomatoes generally don't rot."

Why do you say that when the tissue is already cooked, already filled with ruptured cell walls rapidly turning necrotic, with sugars that have already decomposed within the fruit? That's rotting.

Dave