Iron is not mobile within the plant, and so iron deficiency shows up as pale white new growth. Old growth remains healthy. New white growth is normal size.
Re-greening and new growth in plant (on right side) 4 days after iron addition.
Iron deficiency is characterized by whitening of the new growth. In severe iron deficiency new growth will eventually show signs of deterioration and develop clear areas and then large holes. No old leaf deterioration.