Tomato disease: black spots on leaves

I have 10 cherry tomato plants in my front yard next to my porch in a 8 x 9 area. My neighbor told me to sprinkle powdered milk all over my plants and I did. After a week, the leaves now have black spots on them. They are producing tomatoes. What should I do? Can I still eat my tomatoes when they are red? I grew them from seed in May. This is my first time growing a garden. I worked so hard. They are growing fast.

Tomato Dirt reply:
Congratulations on growing plants from seeds and getting to the point of producing fruit!

Some gardeners use powdered milk or regular milk on tomato plants to prevent or treat blossom end rot.

However, it's unlikely that the powdered milk caused spots on your plants' leaves. Instead, it sounds like your tomato leaves have either Early Blight or Septoria leaf spot - especially if leaves also have some yellowing! You can tell the difference between the two by studying the spots. If they look like they are concentric circles, you probably have Early Blight. Plain black spots are a better indicator of Septoria.

Whether it's Early Blight or Septoria leaf spot, the treatment is similar. Treat organically with copper spray, which you can purchase at the hardware store or home improvement center. Follow label directions. You can apply until the leaves are dripping, once a week and after each rain. Or you can treat with a biofungicide like Serenade. Apply every 7-10 days.

Yes, even when leaves are affected by a disease, your tomatoes are still edible! Just make sure you wash them thoroughly, especially if you treat them.

Tomato plants often recover nicely from blight or leaf spot. We're confident that you'll have a wonderful crop.

Happy Gardening!