Why do tomatoes rot from the bottom?

Question

water daily. bushes look great. green tomaoes look great. they start turning slightly red and they are rotted on the bottom.

Answer 1

Blossom end rot. You can buy calcium nitrate for it but you need to apply it while the plant is in the blooming stage. Waiting until you see rot is too late.

Answer 2

They are laying or touching the ground would be one cause.

Answer 3

Thy have a fungus called bottom end rot. Go to home depot and get the chemical to mix in a sprayer to get rid of it. It will take one or two treatments.