Start / Soil and fertilization / Liming and fertilization
Enter the Ca, Mg, K, potential acidity, and aluminum results from the soil analysis to see base saturation, aluminum saturation, and the ratio between nutrients.
Pre-sizing and estimating tool: the results do not replace a design, calculation, or report signed by a qualified professional, nor verification against the applicable standards.
Technical responsibility. This calculator is under verification. The reference values and examples are hypothetical, to illustrate the calculation, and are not technical references. The user is responsible for the data entered, the choice of parameters, and the use of the results, and must validate them with a qualified professional before any decision, purchase, application, or construction work.
How much of each cation and acidity is in the analysis; the bar shows the value of each component in cmolc/dm³.
Base saturation and aluminum saturation, current and reference; the current V% must reach the target, and the m% must stay below the limit.
Drag the controls to simulate data different from what you entered (from 30% less to 30% more) and watch the result change instantly.
Base saturation (V%) for combinations of calcium and magnesium, with the potassium and potential acidity you entered.
The calculation done in steps, with the values you entered.
The calculation memo gathers this page's inputs, results, equations, assumptions, and references, with fields for project, responsible person, and review. The full report also includes the charts and interpretations, in color. In the print window, choose Save as PDF.
Copy from the report the values for calcium, magnesium, potassium, potential acidity (H+Al) and aluminium. Confirm the unit for potassium and enter the V% target for the crop. The calculator shows the sum of bases, the CTC, base saturation and aluminium saturation, and compares them with the targets.
Ca = 3.2; Mg = 1.1; K = 0.25; H+Al = 4.0; Al = 0.1 (cmolc/dm³), with a V% target of 60%.
SB = 3.2 + 1.1 + 0.25 = 4.55. T = 4.55 + 4.0 = 8.55. V% = 4.55 ÷ 8.55 × 100 = 53.2%, below the target of 60%. m% = 0.1 ÷ (0.1 + 4.55) × 100 = 2.2%, within the limit.
To convert the V% difference into tonnes of limestone, use the liming calculator.
It is the percentage of CEC occupied by the bases (Ca, Mg and K). The higher it is, the lower the soil acidity. The target depends on the crop and region.
Excess exchangeable aluminium is toxic to roots. m% shows the fraction of the effective CTC occupied by Al; above the limit, liming must also correct the aluminium.
Divide by 391. For example, 98 mg/dm³ of K equals 0.25 cmolc/dm³.
Not directly. It shows how far the saturation is from the target. The amount of limestone is calculated in the liming calculator, with PRNT and the correction depth.
Important notice: the Agrocalcs tools make estimates and preliminary sizing based on the data entered and on published engineering methods. They do not replace a design, a calculation report or a report signed by a qualified professional (CREA/ART), nor verification against the applicable technical standards and legislation, such as the Regulatory Standards of the Ministry of Labor. Material and fuel properties vary: check with the manufacturer or with analyses of your process before deciding. By using the site, you agree to the Terms of Use.
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