Amendment Needed
37.5 lbs
Direction
Raise pH (add lime)
Applications
1
Loam is the most common garden soil – moderate buffering capacity.
| Soil Type | Lime (lbs) | Sulfur (lbs) |
|---|---|---|
| Sandy | 25–30 | 10–12 |
| Loam | 70–80 | 20–25 |
| Clay | 120–150 | 45–60 |
Inputs
Result
Loam soil needs 75 lbs of calcitic lime per 1,000 sq ft to raise pH by 1.0 unit. Over 5,000 sq ft that is 375 lbs total, split into 2 applications since 75 lbs exceeds the 50 lbs/1,000 sq ft maximum per application.
Inputs
Result
Sandy soil needs 11 lbs of elemental sulfur per 1,000 sq ft to lower pH by 1.0 unit. For a 1.5-unit drop over 200 sq ft, that is 16.5 lbs per 1,000 sq ft or 3.3 lbs total. Apply 3–6 months before planting.
Inputs
Result
Clay soil needs 135 lbs of base lime per 1,000 sq ft per pH unit. With pelletized lime at 95% effectiveness, that becomes 213.2 lbs/1,000 sq ft for a 1.5-unit change. Over 500 sq ft that is 106.6 lbs, split into 5 applications of about 21.3 lbs each.
The amount of lime depends on your soil type. Sandy soils need 25–30 lbs per 1,000 sq ft, loam needs 70–80 lbs, and clay soils need 120–150 lbs of calcitic lime to raise pH by one full unit. Heavier soils have more buffering capacity and resist pH changes.
| Soil Type | Lime (lbs/1000 sq ft) | Sulfur (lbs/1000 sq ft) | Buffering |
|---|---|---|---|
| Sandy | 25–30 | 10–12 | Low |
| Loam | 70–80 | 20–25 | Medium |
| Clay | 120–150 | 45–60 | High |
Blueberries thrive at pH 4.5–5.5. Use elemental sulfur to lower pH: sandy soil needs 10–12 lbs per 1,000 sq ft per pH unit, while clay needs 45–60 lbs. Sulfur takes 3–6 months to react, so apply in fall or early spring and retest before planting.
| Sulfur Type | Effectiveness | Speed | Cost/lb |
|---|---|---|---|
| Elemental Sulfur | 100% | Slow (3–6 mo) | $0.20 |
| Iron Sulfate | 33% (need 3x) | Medium (1–3 mo) | $0.10 |
| Aluminum Sulfate | 20% (need 5x) | Fast (weeks) | $0.08 |
Calcitic lime is pure calcium carbonate with 100% effectiveness for raising pH. Dolomitic lime contains both calcium and magnesium carbonate, making it 95–108% effective while also supplying magnesium. Choose dolomitic if your soil test shows low magnesium levels.
Lime typically takes 2–3 months to show measurable pH changes and may take 6–12 months for full effect. Finely ground lime reacts faster than coarse or pelletized forms. Hydrated lime works within weeks but can burn plants if over-applied.
| Lime Type | Initial Change | Full Effect | Risk Level |
|---|---|---|---|
| Hydrated | 2–4 weeks | 2–3 months | High (can burn) |
| Calcitic (ground) | 2–3 months | 6–12 months | Low |
| Pelletized | 3–4 months | 6–12 months | Very low |
It is best to wait 2–4 weeks between lime and fertilizer applications. Lime can react with nitrogen fertilizers, especially ammonium-based ones, causing nitrogen to escape as ammonia gas. Apply lime first, then fertilize after a few weeks.
Soil type determines buffering capacity — the soil's resistance to pH change. Clay soils have high cation exchange capacity (CEC) with many charged particles that hold onto nutrients and resist change. Sandy soils have low CEC, so less amendment changes pH quickly but leaches faster.
Read our guide
Read our guide
Read our guide
Discover tools for composting, irrigation, raised beds, seed spacing, and more.
Last Updated: Mar 9, 2026
This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.