Build a Custom Fertilizer Blend

How nutrient-rate calculations work

Multiply the product rate in pounds per 1,000 square feet by the nutrient percentage written as a decimal. Coverage from one 50 lb bag equals 50 divided by the product rate, multiplied by 1,000.

Worked example: 29% nitrogen

At 3 lb of a 29-0-7 product per 1,000 square feet, nitrogen delivered is 3 × 0.29 = 0.87 lb N per 1,000. A 50 lb bag covers 50 ÷ 3 × 1,000 = about 16,667 square feet.

Worked example: 17% nitrogen and 34% potash

At 3.5 lb of a 17-0-34 product, nitrogen is 3.5 × 0.17 = 0.595 lb and K₂O is 3.5 × 0.34 = 1.19 lb per 1,000 square feet. The bag covers about 14,286 square feet.

Worked example: total nutrient in a bag

A 50 lb bag of 20-23-15 contains 10 lb total N, 11.5 lb available phosphate (P₂O₅), and 7.5 lb soluble potash (K₂O). These label values are fertilizer-analysis units, not elemental phosphorus and potassium.

Open the blend calculator

Use the dedicated calculator to configure a custom granular fertilizer blend, then confirm the result with the TurfBeard team and all applicable requirements.

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