Role of Magnesium in Onion Production

Magnesium is required for many processes including transfer of energy and protein synthesis. With 20-25% of the plant’s total magnesium localized in the chloroplasts, it is particularly important for chlorophyll production.

Magnesium effect at growth stages

Stage Magnesium effect
Vegetative Growth Maintain vigorous, healthy leaf growth and to build plant supplies prior to bulbing
See more on Onion Growth Stages.

General guidelines for Magnesium application

Onions crops use relatively low levels of magnesium. Nonetheless, a regular supply is needed throughout the life of the crop. Particular care is needed in fertigation systems to ensure that magnesium, potassium and calcium are balanced.

Magnesium deficiencies in onion

Older leaves turn a uniform yellow along their entire length due to lack of chlorophyll. Leaves can exhibit pale lesions on leaf tips.