Why do my tomatoes leaves keep turning yellow?

why do the leaves on my tomatoes keep turning yellow with black spots then die . They did the same thing last year.
  4 answers
  • Janet Pizaro Janet Pizaro on Jun 01, 2017
    Did you rotate the crop? Black spots are a fungus from improper watering? What was the processed used while trying to grow the tomatoes?

    • Jani Jani on Jun 02, 2017
      I have a raised garden box so I didn't rotate this year. I usually water once a week unless it is really hot and dry or we have plenty of rain.

  • Janet Pizaro Janet Pizaro on Jun 02, 2017
    Crops need to be rotated every year.In the mean time apply a fungicide for tomatoes

  • Jani Jani on Jun 03, 2017
    Thanks. I will try that.

  • Cori Widen Cori Widen on Jun 04, 2017
    Definitely try a fungicide - sounds like that's for sure the problem.