I'm pretty sure it is iron.looks like an iron or CO2 deficiency, for the want of a better explanation, any ideas?
I don't think it is potassium (K), just because it is the new leaves effected. Iron (Fe), or manganese (Mn), are non-mobile in the plant, and deficiencies effect newer leaves.Also could be an early sign of potassium deficiency..
Hi TimThanks Darrel.
I've been dosing regularly but evidently not enough.
Unless...surely my TNC can't be out of date...can it?
I've had it about 14 months.