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Leafy-veg micronutrients: a foliar spray is not a substitute for fixing the soil

A yellow new leaf can be iron, manganese or a drowned root.

Nutrient shortage
Speed
  1. Spray injury has a spray history, twisted irregular spots.
  2. Salt injury scorches margins with white crust, often a whole sheet.
  3. Don’t live on the knapsack; don’t double the concentration.
  4. Foliar micronutrient: The labelled lower rate. First aid
  5. Name what you see before you feed.
  6. If leaves, roots and the surface disagree, stop.
  7. Leafy greens are children — lack writes on the face at once.
  8. A spray is aspirin.

What you see in the field

Heart-leaf scorch, split petioles, new-leaf yellow with green veins; a spray helps, then it returns.First the leaf position: new or old, even yellow or between the veins. If that does not match, do not fertilise yet. Pull one plant and read whether the roots are white, brown or foul.

A sketch. Do not fertilise from the picture alone.

Tap to enlarge. The caption says what to photograph. Missing field photos are marked as to-be-added.

Why it looks like this

The field looks like this because the root cannot take water or nutrients the usual way. Fix the soil condition first — drainage, salt, acidity, compaction or a salt of fertiliser — then a thin feed. Rates live in the range on this page; confirm with a local station and the label.

Easy to mix up

  • Looks like “Spray injury”

    Spray injury has a spray history, twisted irregular spots.

  • Looks like “Salt injury”

    Salt injury scorches margins with white crust, often a whole sheet.

Do this / don’t do that

  1. 1Compare the worst plants with a neighbour ridge. Photograph whole plant, close-up and soil surface before you add fertiliser.
  2. 2Match roots, leaves and the soil surface to this guide. If they do not line up, do not copy a bag count.
  3. 3Use the rate range on this page only as a range. Confirm with a local station and the product label.

Don’t do this first

  • Don’t live on the knapsack; don’t double the concentration.

Rate range

Foliar micronutrient

The labelled lower rate

First aid.

Soil EC / pH

Follow the local leafy-green safety band

This is the meal.

These are ranges. Confirm with your local extension station and the product label.

EC

Whether the house is salty

Leafy greens at seedling are more afraid.

Available B / Ca / Fe

Whether a micronutrient should go in the soil

Follow a soil test.

When you see Heart-leaf scorch, test. Walk an S and mix — one hole is not the field.

Lesson video

2026-03-02 · Li Zeyu · For learning. Serious damage: local agronomist or a soil test.

For learning only. Fertiliser and pesticide decisions need a local agronomist and a soil test.

Not sure? Photograph the field to identify the problem