Leaves can hint at a fertiliser, they cannot replace a soil test

What you see in the field

A leaf can hint. It does not replace a soil test. A sketch — don’t fertilise from the picture alone.Leaf colour is a clue; the sheet is the ledger. A sketch — don’t 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 “Telling yellow leaves apart”

  A tell-apart page only sorts the road; this page says you still test the soil after you sort it.

• Looks like “A foliar-micronutrient advert”

  Spraying a leaf does not change the soil.

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.

Rate range

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

When you see Hold the yellow leaf against the lab sheet. Colour is a clue; the sheet is the ledger, test. If the leaf and the soil disagree, test before you pour.

Lesson video