About this calculator
How much grass seed to buy for a new lawn or overseeding, using typical sowing rates for each seed type.
How it’s calculated
Seed (kg) = area × rate (g/m²) ÷ 1,000. Kikuyu is sown at about 7 g per m² (70 g covers 10 m², and 1 kg about 140 to 150 m²); the rate on the pack takes priority. Many South African lawns are planted as instant lawn or runners instead.
Worked example
With these inputs:
- Area shape
- Rectangle
- Length
- 10 m
- Width
- 8 m
- Seed type
- Kikuyu (coated seed)
the result is:
- Seed needed
- 0.56 kg
Tips from the trade
- Split the seed in half and sow in two directions for even cover.
- Keep the seedbed moist (not soaked) until the grass is established.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and SANS 10400 (the National Building Regulations) and your local municipality before ordering.