Why is my garlic turning yellow?

Garlic yellowing has two scenarios. Natural: lower leaves yellow from April onwards as bulbs mature — this is the harvest signal, not a problem. Premature: yellowing in January–February indicates overwatering (white rot fungus — remove affected plants; no treatment), nitrogen deficiency (apply fish emulsion), or thrips infestation (silvery streaks on leaves — spray neem oil). Check soil moisture first: garlic in waterlogged containers yellows and collapses rapidly.