How much grass seed do I need for 100 square metres?
To cover 100 square metres, you need about 3.42 kg of grass seed for a new lawn — a typical tall-fescue rate — or about 1.71 kg to overseed a thin existing lawn. Across common grass types the new-lawn amount ranges from 0.73 kg to 3.91 kg.
Grass seed for 100 m², by grass type
| Grass type | New lawn (kilograms) | Overseeding (kilograms) |
|---|---|---|
| Tall Fescue | 3.42 kg | 1.71 kg |
| Kentucky Bluegrass | 1.22 kg | 0.73 kg |
| Perennial Ryegrass | 3.91 kg | 1.95 kg |
| Bermuda | 0.73 kg | 0.49 kg |
| Generic / mixed | 2.44 kg | 1.22 kg |
Rates are typical U.S. cooperative-extension ranges (mid-range), applied to 1,076 sq ft. Your seed bag's label is the authority — read it and adjust, and buy about 5–10% extra for edges and thin spots.
Frequently asked questions
How much grass seed do I need for 100 square metres?
For 100 square metres, plan on about 3.42 kg of grass seed for a new lawn, or about 1.71 kg for overseeding, using a typical tall-fescue rate. The exact amount depends on the grass type — across common cool- and warm-season grasses the new-lawn figure ranges from 0.73 kg to 3.91 kg. Enter your real dimensions in the calculator above to get a number for your specific lawn and seed.
Does the grass type change how much seed I need for 100 m²?
Yes — a lot. Fine, spreading grasses like Kentucky bluegrass need far less than bunch grasses. For 100 m², a new lawn needs about 1.22 kg of Kentucky bluegrass but about 3.91 kg of perennial ryegrass. The table on this page lists every common grass type so you can match your seed bag.
How is the grass seed amount for 100 m² calculated?
Seed is applied at a rate in pounds per 1,000 square feet, so pounds = rate × (area ÷ 1,000). This page works from 1,076 square feet; enter your own dimensions above — in feet, yards or metres — and the calculator does the arithmetic, including the metric conversion, for you.
Are these seeding rates exact?
They are typical U.S. cooperative-extension ranges, chosen mid-range and rounded for a planning estimate. Your seed bag's label is the real authority: it gives the exact rate for that blend and whether it is a new-lawn or overseeding rate. Always read the bag and adjust, and buy about 5–10% extra for edges and thin spots.
Grass seed for other sizes
For 1,000 sq ftFor 1 acreFor 2 acresFor ½ acrePer square footPer square metreTo overseed New lawn vs overseeding Full calculator →