Soil and irrigation-water testing: the step that comes before buying anything
Quick answer
A soil test tells you what your soil currently holds and how available it is. An irrigation-water analysis tells you what you are adding to that soil every time you water. They are different tests answering different questions, and in a region dependent on irrigation the second is at least as important as the first. Both come before buying a product, not after it disappoints.
Why testing precedes buying
Feeding without a test may add a nutrient already present while leaving the real shortage untreated. Worse, on a salt-affected soil, over-application adds salts to a soil already loaded. FAO treats measurement as foundational: optimising soil pH is a precondition for the success of nutrient management for crop production — and pH is known only by measuring it.
What a soil test should cover for fertiliser decisions
- pH — decides how available nutrients are, not just whether they are present.
- Electrical conductivity of the saturation extract (ECe) — the salinity measure. A soil is classed as saline above 4 dS/m at 25°C.
- Available nutrients — what the plant can actually reach.
- Organic matter — low in arid soils, and it drives nutrient storage capacity.
- Texture — governs water holding and leaching behaviour.
What a water analysis adds
The water is a renewing input. Whatever it carries accumulates in the soil season after season. The specific reason to test it here is boron: FAO records boron toxicity arising where irrigation water is rich in boron, above 1–2 ppm, and lists an occasional excess of soluble salts, adsorbed sodium and boron among the problems of arid soils.
That makes boron the one nutrient where a well-meant corrective application can do real harm. It should never be added on assumption in this region — only after a water analysis establishes the need.
A sensible order
- Decide what you are trying to answer. A general baseline, or a specific problem on a specific plant?
- Sample from the area in question, not from a convenient spot elsewhere.
- Request pH and ECe explicitly — a basic nutrient panel may omit them, and they are the two that explain most local problems.
- Test the irrigation water separately, including boron and chloride.
- Read the results with the label, not instead of it. The product label remains the binding authority on quantity.
In Kuwait's conditions
Two properties of arid-region soils make testing unusually informative here. They are neutral to slightly alkaline, so micronutrient availability — not supply — is often the limiting factor. And they are frequently salt-affected, so a nutrient reading alone can be actively misleading without an ECe figure beside it.
A soil analysis showing adequate nutrients alongside a plant that looks starved is itself a diagnosis: the problem is availability, salinity or roots, not supply.
Evidence limitation: we could not reach a Kuwait institutional source — PAAF was unreachable and KISR publishes no extension guidance — so we state no local sampling protocol, no local threshold and no local rate.
Common mistakes
- Testing the soil and never testing the water.
- Omitting pH and ECe from the request and receiving only a nutrient list.
- Sampling from an unrepresentative spot.
- Adding boron because a plant sets fruit poorly, without a water analysis.
- Treating a test result as a prescription. It is an input to a decision, not the decision.
Boundary
We name no laboratory, quote no price, and give no sampling depth or procedure — sampling method genuinely affects the result, and no institutional protocol from a reachable Kuwait source was available to cite. Interpreting a result into an application is a specialist's job, working from your figures and the product label.
Related glossary terms
Sources
- FAO — Fertilizer and Plant Nutrition Bulletin 16, Chapters 3, 4 and 7.
- FAO — Soils Portal: Salt-affected soils.
All accessed 26 August 2026. Last reviewed: 27 August 2026.