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Calcimator

Fertilizer Application Rate

Calculate the pounds per acre of nitrogen, phosphorus, and potassium to apply based on soil test results and crop nutrient requirements.

Inputs

ppm
ppm
ppm
lbs/acre
lbs/acre
lbs/acre
acres

Results

Nitrogen to Apply

130 lbs/acre

P2O5 to Apply20 lbs/acre
K2O to Apply0 lbs/acre
Estimated Cost per Acre$83.50
Total Fertilizer Cost$13,360.00
How to Use This Calculator
  1. Enter the crop type and yield goal in bushels per acre.
  2. Input current soil test values for nitrogen, phosphorus, and potassium.
  3. Set the fertilizer product and its nutrient analysis (N-P-K percentages).
  4. Review recommended application rate per acre and total product needed for the field.
  5. Compare to soil test recommendations and adjust for manure credits if applicable.

How the result changes with Crop N Requirement

Crop N RequirementNitrogen to Apply
300 lbs/acre
10575 lbs/acre
195165 lbs/acre
270240 lbs/acre

What each input means

Soil Nitrogen (NO3)
Nitrate-nitrogen level from your soil test report in parts per million.
Soil Phosphorus
Available phosphorus (Olsen or Bray P1) from your soil test in ppm.
Soil Potassium
Exchangeable potassium from your soil test in ppm.
Crop N Requirement
Total nitrogen the crop needs in lbs per acre. Corn: 140-200; wheat: 80-120; soybean: 0 (fixes own N).
Crop P2O5 Requirement
Phosphorus (as P2O5) the crop needs in lbs per acre.
Crop K2O Requirement
Potassium (as K2O) the crop needs in lbs per acre.
Field Size
Total field area in acres for calculating total fertilizer tonnage.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Soil Nitrogen (NO3) = 15, Soil Phosphorus = 20, Soil Potassium = 150, Crop N Requirement = 160 = 7 input(s) provided
  2. Calculate Nitrogen to Apply
    Nitrogen to Apply
    130 = 130
  3. Calculate P2O5 to Apply
    P2O5 to Apply
    20 = 20
  4. Calculate K2O to Apply
    K2O to Apply
    0 = 0

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