Seed needed = Area × Rate per 1000 sq ft / 1000
Seeding rates vary by grass species and whether you're establishing a new lawn or overseeding. New lawn rates are typically 2× overseeding rates. Cool-season grasses (bluegrass, fescue, ryegrass) are best seeded in early fall (soil temps 50-65°F). Warm-season grasses (bermuda, zoysia) seed in late spring. Steps for new lawns: grade and level soil, add 2-4" of topsoil/compost, rake smooth, apply seed with a broadcast spreader, cover lightly with straw mulch, water gently 2-3× daily until germination (7-21 days depending on species). Avoid mowing until grass reaches 3" tall. Overseeding: mow low, dethatch, spread seed, topdress with compost, keep moist.