Lawn seed and turf calculator

The standard seeding rate is 20–50 g/m², depending on the grass mix. Garden lawns are typically sown at 30–40 g/m², sports and recreational turf at 35–50 g/m², and shade-tolerant mixes at 20–30 g/m². Always check the rate on the seed packaging.

Seeding is cheaper (a few PLN per m²) but requires more time and care during the first few weeks. Turf gives near-instant results and can be walked on after 2–3 weeks, but costs several times more. Seeding works best for large areas; turf is ideal when a quick, neat finish matters.

The seeding rate is the recommended amount of seed in grams per square metre. Too low a rate results in thin, weedy turf; too high wastes seed and can slow germination through overcrowding. Stick to the manufacturer guidelines.

The ideal sowing times are spring (April–May) and late summer (August–September). In spring the soil warms quickly for fast germination; in autumn the grass has time to root before winter. Avoid sowing during drought, extreme heat or frost. Soil temperature should be at least 8–10°C.

Buy about 5–10% more seed than the calculation shows to cover sowing losses, patchy germination and areas that need reseeding (touch-ups). The calculator automatically adds a 5% reserve to its result.

Dig or rotovate the soil to 15–20 cm, remove weeds and stones, then level and lightly firm it. Improve heavy soils with sand or add compost, and apply a pre-seeding lawn fertiliser. Wait a few days for any weed seedlings to emerge, then remove them before sowing.

A standard turf roll typically measures 1 m × 0.4 m (0.4 m²) or 1 m × 0.5 m (0.5 m²). For 100 m² you need roughly 200–250 rolls. At 5–15 PLN per roll the material cost is approximately 1000–3750 PLN for 100 m². Seeding is several times cheaper.

After seeding, water gently every day for the first 2–3 weeks until the seeds germinate. The soil should stay lightly moist but not waterlogged. After laying turf, water thoroughly immediately, then daily for the first two weeks. Freshly laid turf can die quickly if watering is missed in the early days.

First mow when the grass reaches 8–10 cm — usually 4–8 weeks after sowing. Set the mower to 5–6 cm and never remove more than one-third of the blade length at a time. Cutting too early or too short can damage a young lawn.

Divide the irregular plot into simpler shapes (rectangles, triangles), calculate each section separately and add them up. You can also use a land-area calculator or a map tool (Google Maps can measure areas). Then enter the total area into the lawn calculator and add 10–15% extra for irregular edges.