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pH

pH is a measurement, not a disease.

Also called: acidity, water pH, 1:2.5 pH, pH 5.2

Speed
  1. pH is a measurement, not a disease.
  2. Acidity and water pH on the sheet are the same cell.
  3. Read the soil to water ratio before you compare labs.
  4. On grain land, lime only below about 5.5.
  5. Do not push tea to neutral.
  6. Above about 8, iron often locks.
  7. Rates live in the acid-soil and lime guides.

How it appears on the sheet

The sheet may say pH, acidity, or water pH. Read the soil:water ratio first. Different ratios are not the same number.

A sketch. Do not fertilise from the picture alone.

Common units

Dimensionless. Soil:water is often 1:2.5 or 1:1 — read the note, don’t mix labs.

Soil:water ratio · 1:1, 1:2.5 and 1:5 pH are not the same number.

How to read the number

pH is a measurement, not a disease. Lime or alkali amendments aim at this number. Grain land and tea have different targets.

If the number and the field disagree, read the soil:water ratio first. Rates live in the field guide.

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

Low / mid / high (sketch)
CellLowMidHigh
Grain, water pH (sketch)Below about 5.5, root tips brownAbout 6.0–7.5 for most grain and vegAbove about 8, iron locks
TeaToo low hurts rootsAbout 4.5–6.0 is the tea windowDo not push tea to neutral

Regional classes differ. This table is a comparison, not a prescription.

What it looks like in the field

Brown bald root tips often match low pH on grain land; yellow new leaves with green veins often match high pH. Tea uses a different range.

Don’t do this

  • Don’t mix labs or soil:water ratios.
  • Don’t push tea to neutral.
  • pH is not a nutrient name.

Lesson video