How much fertilizer do I need per 1000 square feet?

It depends on the fertilizer NPK ratio and your desired nitrogen rate. For most lawns, apply 1 lb of nitrogen per 1000 sq ft per application. With a 20-5-10 fertilizer, that means 5 lbs of product per 1000 sq ft.

What do the NPK numbers mean?

Fertilizer bag grades use N–P₂O₅–K₂O: nitrogen (N), phosphorus reported as phosphate (P₂O₅), and potassium reported as potash (K₂O), each as a percentage of product weight. A 10-10-10 bag has 10% nitrogen, 10% phosphate equivalent, and 10% potash equivalent—not 10% elemental phosphorus and potassium.

How often should I fertilize my lawn?

Cool-season lawns benefit from 3-4 applications per year (primarily fall and spring). Warm-season lawns typically need 2-3 applications during their active growing season in summer.

Can I use too much fertilizer?

Yes! Over-fertilizing can burn your lawn, harm plants, and pollute waterways. Always follow recommended application rates and never exceed them.

What is the best fertilizer for a new lawn?

For new lawns, use a starter fertilizer with higher phosphorus (the middle number), like 5-10-5. Phosphorus promotes root development. Apply at half the normal nitrogen rate.

Plant Reference

Tools & Calculators

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