Fe concentration used for foliar spray is

Fe concentration used for the foliar spray is 0.4%.
The application of foliar sprays is a common means of correcting Fe deficiency in crops. Applying chelated iron to the soil is the most effective way of correcting yellow leaves as it requires just a single application.
Foliar spray is used when rapid response is needed to correct a chlorotic condition. A foliar spray with iron sulphate or iron chelate solution may be applied when the tree is in full leaf.