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Magnesium Deficiency in Onion: Symptoms, Causes & How to Fix It

A complete agronomist guide to identifying and correcting Magnesium deficiency in Onion crops. Includes visual symptom guide, soil test interpretation, and fertilizer recommendations.

Why Onion Needs Magnesium

Magnesium is an essential nutrient for Onion growth and development. Magnesium is the central atom of chlorophyll. Deficiency directly reduces photosynthesis.

In India, Magnesium Deficiency is particularly common in Onion grown in Maharashtra, Karnataka, Gujarat due to specific soil conditions in these regions.

Visual Symptoms of Magnesium Deficiency in Onion

🔍 What to look for in your Onion field:

⚠️interveinal chlorosis starting from older leaves (stays green near veins)
⚠️reddish purple tints
📊 Did you know? Magnesium is the central atom of chlorophyll. Deficiency directly reduces photosynthesis.

Soil Causes of Magnesium Deficiency in Onion

Magnesium Deficiency in Onion is commonly caused by: Sandy soils, high potassium application, acidic soils

A soil test is the most reliable way to confirm Magnesium deficiency. Use SoilPro's NPK Calculator to get fertilizer recommendations based on your soil test values.

How to Correct Magnesium Deficiency in Onion

ProductApplication MethodDoseTiming
Magnesium Sulphate (Epsom Salt) 0.5% foliarFoliar sprayEpsom SaltVegetative stage
MgSO4 soil application (10 kg/acre)Soil10 kg/acrePre-sowing
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Frequently Asked Questions

What are the symptoms of Magnesium Deficiency in Onion?

interveinal chlorosis starting from older leaves (stays green near veins), reddish purple tints

How quickly can I fix Magnesium Deficiency in Onion?

Foliar sprays show improvement in 7-10 days. Soil applications take 2-3 weeks. Severe deficiency may need 2-3 foliar sprays at weekly intervals.

Does Magnesium Deficiency affect Onion yield?

Yes significantly. Magnesium deficiency reduces Onion yield by 20-50% depending on severity. It also reduces fruit/grain quality.

Which soil test should I do for Onion?

Test for pH, EC, N, P, K, Zn, Fe, Mn, B, and organic carbon. SoilPro can interpret any soil test report and give crop-specific recommendations.

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