Hi All,
I planted out my tomatoe plants in the Polytunnel on Saturday - they are flying along and have first trusses on them already, however I noticed today that inbetween the veins on the older leaves is turning yellow. I have been told that this is caused by a magnesium deficiency, will Tomatoe feed sort this for me or do I need to give them Magnesium. Can I just buy Magnesium of do I need to get it in some other formulation?
I would really appreciate help with this.