Calculate Soil Amendment
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Plant pH Preferences
| Plant | Preferred pH | Amendment |
|---|---|---|
| Blueberry, Azalea, Rhododendron | 4.0-5.5 | Sulfur |
| Strawberry | 5.5-6.5 | Sulfur |
| Tomato, Pepper, Bean | 6.0-6.8 | Lime or Sulfur |
| Rose | 6.0-7.0 | Lime |
| Lawn Grass | 6.0-7.0 | Lime |
| Corn, Squash | 6.0-7.5 | Lime |
How to Use This Calculator
Start by testing your soil with a digital pH meter or test kit. Enter the reading in the Current pH field. Choose your target crop or enter a specific pH goal. Input your garden area in square feet.
The calculator uses the formula: pounds of amendment = (pH change × area) ÷ 10. Sandy soils need 25% more amendment. Clay soils need 25% less. Click Calculate to see exact amounts.
Apply amendments in fall for best results. Work them into the top 6 inches. Water thoroughly after application. Wait 2-3 months before retesting.
Common Mistakes
- Applying too much at once. Make gradual changes over months.
- Not testing soil first. Numbers guide the exact amount needed.
- Ignoring soil type. Sandy and clay soils need different rates.
- Applying in summer heat. Spring and fall are better times.
Application Timing
For lime: Apply 2-3 months before planting. Fall applications work best. Water after spreading.
For sulfur: Apply 1-2 months before planting. Works faster in warm soils. Mix into top layer.