🪨 Lime Rate Calculator — Tonnes per Hectare
Calculate lime required to raise soil pH based on current pH, target pH and soil type. Correct soil acidity for better crop yields.
Quick answer: Sand: 1-3 t/ha, Sandy loam: 2-5 t/ha, Loam: 3-7 t/ha, Clay: 5-10 t/ha. Apply 6-12 months before planting acid-sensitive crops like canola or lupins.
🪨 Calculate Lime Requirement
📐 How Lime Rate Is Calculated
Lime (t/ha) = (Target pH − Current pH) × Soil factor
Soil factor: Sand 1.5, Sandy loam 2.5, Loam 3.5, Clay loam 4.5, Clay 5.5
- Get soil test — current pH and buffer pH
- Set target pH — based on crop requirements
- Calculate pH increase needed — target minus current
- Apply soil factor — clay soils need more lime
📊 Worked Example
Loam soil, current pH 5.0, target pH 6.5. Soil factor for loam = 3.5.
pH increase = 6.5 − 5.0 = 1.5
Lime required = 1.5 × 3.5 = 5.25 t/ha
Cost @ $70/t = $367.50/ha
Apply in autumn, incorporate by cultivation. Retest soil after 2-3 years to check response.
❓ Frequently Asked Questions
Lime (t/ha) = (Target pH − Current pH) × Soil factor. Example: Target 6.5, current 5.0, loam factor 3.5 = (1.5) × 3.5 = 5.25 t/ha.
Sand: 1-3 t/ha, Sandy loam: 2-5 t/ha, Loam: 3-7 t/ha, Clay: 5-10 t/ha. Apply 1-2 years before planting acid-sensitive crops.
Agricultural lime (calcium carbonate) $40-80/t. Dolomite (adds magnesium) $50-100/t. Use finer mesh (80% passing 100 mesh) for faster reaction.
Apply 6-12 months before sowing. Autumn application on dry soil allows winter rain to incorporate. Lime moves slowly (1-2cm/year).