Role of Iron in Onion Production
Iron is associated with chlorophyll formation and photosynthesis.
Iron deficiency
Iron effect at growth stages
Stage | Iron effect |
Vegetative Growth | Ensure photosynthetic growth is not limiting |
Bulb Formation | To maintain leaf growth |
Bulb Fill | Less critical, but to maintain growth and prolong bulking |
See more on Onion Growth Stages.
General Guidelines for Iron Application
Applications of iron, such as foliar or fertigation, can be used to increase early leaf production and crop productivity.
Iron Deficiencies in Onion
Generally, onions appear insensitive to iron deficiency, with most soils supplying adequate levels of iron to meet crop needs. Under extreme deficiencies, leaves become completely chlorotic and bleached.