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Potassium (K)

Potassium runs water use and quality. The word is K; split scorch from white crust first.

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  1. Potassium (K)。
  2. Potassium runs water use and quality. The word is K;。
  3. split scorch from white crust first.。
  4. Deficiency: old-leaf margins scorch like fire. The surface need not be white. Salt scorches too。
  5. usually with frost.。
  6. Deficiency: old-leaf margins scorch like fire. The surface need not be white. Salt scorches too。
  7. usually with frost.。

How it appears on the sheet

Deficiency: old-leaf margins scorch like fire. The surface need not be white. Salt scorches too, usually with frost.

A sketch. Do not fertilise from the picture alone.

Common units

Total K often g/kg.

How to read the number

Deficiency: old-leaf margins scorch like fire. The surface need not be white. Salt scorches too, usually with frost. High-yield fields export a lot. Straw returns K. Chloride-sensitive crops prefer sulfate of potash Easy to mix up: Salt, chloride and drought all scorch margins. Read the surface and the root before you say K Potassium runs water use and quality. The word is K; split scorch from white crust first.。

Thresholds only, not a prescription. Rates live in the field guide. This page does not hand you a bag count.

What it looks like in the field

Deficiency: old-leaf margins scorch like fire. The surface need not be white. Salt scorches too, usually with frost.

Don’t do this

  • Scorch treated as salt when the surface is not white.
  • Straw hauled off, then blaming the soil for no K.
  • Salt, chloride and drought all scorch margins. Read the surface and the root before you say K.

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