What Soil Testing Reveals About Coffee Farms — And Why It Matters
Before GAP77™ practices begin, soil sampling reveals the baseline: depleted nutrients, high acidity, and missing microbiology. Here's how F.O.C.U.S.™ tests and tracks soil health.
Every F.O.C.U.S.™ programme begins with the same step: understanding what’s actually in the soil. Before any GAP77™ practices are implemented, systematic soil sampling establishes a baseline — and the results consistently tell the same story across coffee-growing regions.
What the sampling reveals
Years of soil testing across five countries have shown a common pattern:
- High acidity / low pH — limiting nutrient availability to coffee trees
- Imbalanced NPK — nitrogen, phosphorus, and potassium out of proportion
- Low electroconductivity — indicating poor nutrient-carrying capacity
- Missing microbiology — the nematodes, protozoa, and mycorrhizal fungi that healthy ecosystems depend on are absent or depleted
These aren’t unusual findings. They’re the predictable result of decades of poor land management and, in some cases, excessive chemical fertiliser use that has disrupted natural soil systems.
How samples are collected
Soil samples are collected using a W-formation pattern across each farm — 5 sample points distributed in a W shape to ensure representative coverage of the plot. At each point, 3 nested samples are taken using a soil cylinder auger at 30cm depth.
This stratified approach ensures statistical reliability. A single sample from one corner of a farm tells you very little. Five points in a W pattern, with nested samples at each, gives you a genuine picture of the farm’s soil condition.
What’s tested
Each sample is analysed using SDK (Soil Diagnostic Kit) field testing for:
- Nitrogen content — essential for leaf growth and cherry development
- Potassium content — critical for disease resistance and fruit quality
- Phosphorus content — drives root development and energy transfer
- Acidity levels — determines nutrient availability; coffee prefers pH 6.0–6.5
- Electroconductivity — measures the soil’s ability to conduct nutrients to roots
- pH — the baseline indicator of soil health
These field tests provide rapid results that inform immediate management decisions — which plots need lime to correct acidity, where phosphorus is critically low, which areas have the most potential for improvement.
Soil biology under the microscope
Beyond chemical analysis, F.O.C.U.S.™ also examines soil biology. Prepared samples are examined under microscope to assess microbial populations — the living component of healthy soil that most conventional testing ignores.
Healthy soil teems with microorganisms that cycle nutrients, suppress disease, and build soil structure. Depleted coffee farm soils typically lack these populations entirely. Tracking their return after GAP77™ practices are implemented is one of the clearest indicators that regenerative methods are working.
Baseline to benchmark
The initial soil sampling establishes the baseline for carbon measurement. Soil organic carbon at the start of the programme is measured so that future changes — driven by composting, biochar application, cover cropping, and other GAP77™ practices — can be quantified.
This is how additionality is demonstrated: the soil data shows what carbon levels were before intervention, and ongoing monitoring shows what they become after. The bottom 10cm of each 30cm sample is analysed separately to assess carbon permanence — whether carbon is being stored at depth where it’s stable long-term.
Without this systematic soil testing, there’s no credible baseline and no way to verify that carbon sequestration is genuinely happening.
For the full soil measurement methodology, see our methodology. For more on soil context across coffee farms, see our FAQ on why coffee farms are suited to carbon sequestration.
