Spreading agricultural lime is the most reliable way to neutralize acidic soils and free up essential plant nutrients in your garden.
1. Why Soil Acidifies Over Time
Rainfall naturally leaches calcium and magnesium out of topsoil, leaving acidic hydrogen ions behind. Over several seasons, garden soil pH drops below the ideal 6.2 to 6.8 range.
Synthetic nitrogen fertilizers and decomposing pine needles also contribute to gradual soil acidification.
When soil pH falls below 5.5, plants cannot absorb phosphorus or potassium, leading to stunted roots and yellowing leaves.
2. Calcitic vs. Dolomitic Lime Comparison
Calcitic lime contains calcium carbonate and works quickly to neutralize soil acidity without changing magnesium levels.
Dolomitic lime contains both calcium carbonate and magnesium carbonate. Use dolomitic lime if your lab report shows low magnesium numbers.
Pelletized lime is easier to spread with a push spreader than fine pulverized dust, reducing wind drift and mess.
| Lime Type | Primary Nutrient Content & Usage |
|---|---|
| Calcitic Lime | Pure Calcium Carbonate (Use when Mg tests optimum) |
| Dolomitic Lime | Calcium + Magnesium Carbonate (Use when Mg tests low) |
| Pelletized Lime | Dust-free granules bound with water-soluble binder |
🧪 Need Your Soil Tested by an Official University Lab?
Find official land-grant extension office phone numbers, physical sample drop-off locations, and lab fee schedules across all 50 US States.
Find Your County Extension Office →3. Application Rates and Timing
Never apply more than 50 lbs of lime per 1,000 square feet in a single application. If your report requires 100 lbs, split the dose between autumn and spring.
Fall is the best season to spread lime. Winter rain and freezing temperatures help limestone react with soil chemistry before spring planting.
- Test soil pH before applying limestone.
- Choose dolomitic lime if magnesium is deficient.
- Incorporate lime 4 to 6 inches deep into garden beds.
- Re-test soil pH 6 months after application.