Tomato plants going yellow & dying
This is my first year with a new poly-tunnel.
I planted loads of tomato seeds (from the same packet) into trays and when they'd grown large enough I transplanted them into small pots inside the poly-tunnel.
When they were large and healthy enough I planted 11 of the tomato plants inside the poly-tunnel and the rest of them outside in a small plot of their own.
The bed inside the poly-tunnel where I planted the tomatoes had a few large bags of compost (bought from a supermarket) dug in to help the soil.
At the same time as planting the tomatoes I also planted sweet peppers between the tomato plants.
The tomato plants outside are doing just fine but 9 of the 11 plants inside the ploy-tunnel have gone yellow and died and the other two are just hanging on a bit longer
The sweet peppers are doing just fine with no problems.
I don't understand what is happening and no one else on our allotments seem to know either.
Maybe you can shed some light on why the tomato plants in the ploy-tunnel have all but died whereas the ones outside are thriving?
Surely if it was something in the soil the sweet peppers would have suffered as well?