Fertilizer Calculator

The ranges and levels of actions supplied have been successfully used in commercial DWC lettuce operations. They can be changed if you want to target different ranges.

To utilize this calculator, you will need a current water test or nutrient solution test from an accredited lab. Note: This will not supply acidification rates for pH and Alkalinity adjustments.

Step 1: Enter your test results in the corresponding column.

Step 2: The sheet will automatically calculate the additions needed for each element. If the value is negative, no additions are needed for that nutrient.

Step 3: Transfer the values to the associated single element.

• For Phosphorus additions, remember to take into account the added Potassium from the fertilizer and subtract it from your total potassium needs.
• It's best practice to base the Calcium Nitrate and Potassium Nitrate additions on needed Calcium and/or Potassium, but also to avoid exceeding Nitrogen rates.
• For micronutrients, make sure you choose the proper form (Chelated or Sulfated).
• Notes: 25 PPM N from Calcium Nitrate delivers 30.6 PPM Ca, and 25 PPM N from Potassium Nitrate Delivers 70 ppm K

If you have questions, don't hesitate to get in touch with Krystal Snyder at [email protected]