Soil pH Down Calculator
Sulfur Rate to Lower Soil pH
Example soil acidification calculation
This worked example demonstrates how the soil acidification calculator estimates material requirements for reducing soil pH under typical field conditions.
Example input data
- Acidifying material: Elemental sulfur (S)
- Soil texture: Loam
- Tillage system: Full tillage (plowing)
- Application depth: 20 cm
- Current soil pH: 7.2
- Target soil pH: 6.4
- Field area: 4 ha
- Buffer pH: 6.5
- Bulk density: 1.3 g/cm³
Model assumptions & valid input ranges
- Initial soil pH: 5.5 – 8.5
- Target soil pH: ≥ 5.5
- Maximum pH reduction per season: 1.2
- Bulk density: 0.6 – 1.8 g/cm³
- Buffer pH: 3.5 – 10.0
Calculation result
Results are shown per hectare and for the total field area.
Calculated Soil Acidification Requirement
The table below shows the estimated amount of acidifying material and nutrients required to reduce soil pH
| Parameter | Per hectare | Total (4 ha) |
|---|---|---|
| Elemental sulfur (S) | 435.45 kg | 1.74 t |
| Sulphur (S) | 435.45 kg | 1.74 t |
• This calculation estimates the amount of elemental sulfur (s) required to reduce soil pH based on soil texture, application depth, and buffer capacity. Results are estimates — always confirm soil pH with laboratory analysis or field measurements.
Application plan
This table shows a recommended application plan to gradually reduce soil pH based on soil properties, target pH, application depth, and the selected material. Only nutrients supplied by this material are included.
| Application | Per hectare | Total (4 ha) | ||
|---|---|---|---|---|
| Elemental sulfur (S) | S | Elemental sulfur (S) | S | |
| Dose 1 | 263.08 kg | 263.08 kg | 1.05 t | 1.05 t |
| Dose 2 | 172.37 kg | 172.37 kg | 689.46 kg | 689.46 kg |
| Parameter | Dose 1 | Dose 2 |
|---|---|---|
| Per hectare | ||
| Elemental sulfur (S) | 263.08 kg | 172.37 kg |
| S | 263.08 kg | 172.37 kg |
| Total (4 ha) | ||
| Elemental sulfur (S) | 1.05 t | 689.46 kg |
| S | 1.05 t | 689.46 kg |
• Split applications reduce the risk of over-acidification and help stabilize soil pH over time.
• Calculations are estimates. Excessive acidification may increase the risk of nutrient imbalance or aluminum toxicity. Always verify soil pH with laboratory analysis and follow local agronomic recommendations.
This example illustrates a gradual soil acidification strategy using elemental sulphur. Actual soil response depends on temperature, moisture, microbial activity, and soil buffering capacity. Always monitor soil pH after application and adjust management accordingly.
Control Soil pH with Confidence
Plan sulfur applications, track pH changes, and connect all soil calculations in one place
Related Materials
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Blogs
Adjusting Soil pH with Lime: Materials, Rates, and Tillage
Effective soil pH management depends on choosing the right liming materials, applying accurate rates, and adapting practices to tillage and no-till systems
CCE vs ECCE: Understanding Lime Effectiveness in Soil pH Adjustment
Learn how calcium carbonate equivalent and lime fineness determine real-world soil pH correction — and why ECCE matters more than total tonnage
Frequently Asked Questions
- A soil pH down sulfur calculator estimates how much sulfur is required to lower soil pH. It helps determine the correct sulfur application rate based on soil properties such as texture, buffering capacity, and target pH.
