Tomato plants turning yellow at the top of plant not the bottom. What can be causing this?

Question

Tomato plants are in a previous cattle yard.

Answer 1

This sounds like either a calcium or nitrogen deficiency. Since these are in an old cow field, I think it is safe to rule out nitrogen. Since magnesium and calcium affect the uptake of each other, it will be good to add it as well. This can be added in the form of DOLOMITIC LIME. I prefer it over hydrated, or calcitic lime, since it has added magnesium. It is best to test the soil first to see what, and how much you need.

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