Fertilizer NPK Calculator
Turn a soil test into pounds of nutrients per bed.
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Fertilizer & Nutrients — 13 calculators
New Compost Bin Size Calculator
How big a compost bin you need, in cubic feet, from your kitchen scraps and yard waste.
Use ToolNew Nitrogen Fertilizer Calculator
How many pounds of a nitrogen fertilizer to apply to hit your target nitrogen rate for an area.
Use ToolNew Spray Tank Mixing Calculator
How much product and water to load a sprayer for an area, and how many tankfuls the job takes.
Use ToolNew Organic Fertilizer Calculator
Pounds and bags of an organic meal needed to hit a nitrogen target, by product N percentage and price.
Use ToolNew Phosphorus and Potassium Fertilizer Calculator
Pounds and bags of phosphate or potash product to meet a P2O5 or K2O recommendation, with elemental nutrient shown.
Use ToolNew Manure Application Calculator
Size a manure application from nitrogen need, per-ton N content and first-year availability, with food-safety waiting periods.
Use ToolNew Water pH Adjustment Calculator
Sizes a split-dose acid schedule for irrigation or spray water from source buffer strength, gallons and the pH drop you need.
Use ToolNew Gypsum Application Calculator
Reads a texture-by-purpose table for gypsum pounds per 1,000 sq ft, then converts your area into bags, calcium and sulfur, split by pass.
Use ToolNew Soil Test Interpretation Calculator
Enter a soil-test nutrient reading in ppm and the calculator sorts it against published low and high lines into Deficient, Adequate or Excessive, then names the optimal range and the correction.
Use ToolNew Fertilizer Blend Solver
Mix bagged fertilizers into a blend that hits your exact N-P-K target: enter the pounds of nitrogen, phosphate and potash you want, pick two or three products, and the solver finds the closest match and its cost.
Use ToolNew Fertilizer Cost per Nutrient Calculator
Compare any fertiliser on price per pound of nitrogen, phosphate and potash, then cost the real application for your area and rate.
Use ToolNew Compost Tea & Liquid Dilution Calculator
Turn a product analysis and a target ppm nitrogen into millilitres per litre, ounces per gallon and a 1-to-n ratio for the tank you are mixing.
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