Overseeding Calculator — Thicken Your Lawn
Calculate seed rates for patching and thickening existing lawns.
How We Calculate This
Overseeding rates are a fraction of new lawn rates, depending on lawn condition.
Light overseeding (minor thinning): 30% of new lawn rate. Moderate: 50%. Heavy renovation: 70%.
Combined with the seed type rate (General 35g/m², Fine 25g/m², etc.) this gives the grams per m².
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.