I have a couple of matchless determinate variety tomatoes in grow bags. I am from Chennai, India (hot, humid and it's monsoon time now). It's been raining the past week. I applied Monopotassium phosphate (0:52:32) for the first time one day back and it rained out of nowhere in the evening.

Now there are a few black spots beginning to occur in the leaves. I also have these plants that are wilting, and I'm not able to conclusively identify the problem.


  1. Sprayed with Neem oil 2 weeks ago
  2. Sprayed with NPK 19:19:19 2 weeks ago
  3. Rained for 3-4 days this week
  4. Sprayed with MKP 0:52:32 yesterday
  5. Rained heavily

Plants started setting fruit last month.

Plant 2 enter image description here

I searched "sudden outbreak of yellow leaves on tomato and other plants" and found a link about septoria leaf spot. I looked at that, will probably follow the tips next time onwards.

Soil Medium and fertilizer I am using: Cocopeat (30%), Red Sand (30%), Cow Dung Manure (20%) & Vermicompost (20%) and some gypsum. Been using balanced NPK once each 3 weeks.

  • tomatodirt.com/septoria-leaf-spot.html
    – dj_stat
    Commented Nov 5, 2015 at 3:15
  • 1
    you should make an answer out of that since it is most like the exact problem.
    – Escoce
    Commented Nov 5, 2015 at 14:15
  • I concur that it looks like septoria (but I'm not an expert on septoria). However, I should note that I have a Purple Beauty bell pepper that had similar recurring symptoms, as well as spider mites, and since I gave it some sea minerals, the problems haven't really been much of a problem, again, yet (even without taking my previous measures against spider mites). I need to give it some more time, though. Commented Nov 6, 2015 at 0:40


Browse other questions tagged or ask your own question.