Seven reasons tomato leaves turn yellow, in one look at the leaf: natural ageing, nitrogen, water and roots, magnesium, early blight, Septoria and the wilts. The full video has the fix for each one.
Yellow leaves on a tomato plant.
A few old leaves at the bottom, on a healthy plant: that's natural ageing. Evenly pale, and creeping upward: nitrogen. Yellow and wilting in wet soil: water and roots. Yellow between green veins: magnesium. Spots with target rings: early blight. Lots of tiny spots: Septoria. One-sided yellowing and wilting: Fusarium or Verticillium. If this helped, subscribe for more practical crop guides, and tell me in the comments what you're growing this season.
Yellow leaves on a tomato plant can mean anything from "completely normal" to a soil-borne disease. This video walks through the 7 most common causes, how to tell them apart from the leaf itself, and what to do about each one.
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