A new lawn is mostly preparation. Get the ground right and both turf and seed will succeed. Get it wrong and neither will: a lumpy, compacted, poorly drained base gives a patchy lawn however good the grass is.
Turf or seed?
| Turf | Seed | |
|---|---|---|
| Cost | Higher | Much lower |
| Usable | In a few weeks | In a few months |
| Weeds | Few at first | More, until established |
| Labour | Heavy, but fast | Light, but needs care for longer |
| Grass choice | Whatever the farm grows | Any mix you like |
| Timing | Most of the year | Best in the right season |
Clients who want an instant result usually choose turf. Large areas, shady spots and tight budgets often suit seed.
Prep
- Clear weeds and debris, ideally a few weeks ahead so regrowth can be dealt with.
- Break up compacted ground by rotavating or forking.
- Add 100–150 mm of screened topsoil where the existing soil is poor or the levels need building up.
- Rake level, firm the surface by treading or rolling, and rake again until it's even.
- Apply a pre-seed or pre-turf fertiliser.
- Water the ground a day or two before laying if it's dry.
Get the levels right before laying, sloping gently away from buildings. It's far harder to fix dips and bumps once the grass is down.
Turf: quantities
Instant turf is sold by the square metre, in rolls or slabs, and usually delivered on pallets of about 50–60 m². Order the area plus 5% for trimming curves and edges. Lay it within a day of delivery. In warm weather it heats up and yellows quickly on the pallet.
Lay in a brick pattern with staggered joints, butt edges tightly without stretching, and work from boards so you don't dent the prepared soil. Water thoroughly the same day, then keep it moist until it roots, usually two to three weeks.
Seed: quantities
Rates depend on the grass: couch about 10 g/m², kikuyu about 5 g/m², tall fescue about 35 g/m² and perennial ryegrass about 40 g/m² for a new lawn. Buffalo and zoysia are usually laid as turf rather than sown. Check the pack for its recommended rate. Split the seed in half and sow in two directions at right angles for even cover, then lightly rake it in and roll.
Keep the surface moist (not soaked) until the seed germinates and the grass is established. Birds love fresh seed, so a net or fleece can help on small areas.
Timing
Warm-season grasses (couch, kikuyu, buffalo, zoysia) cover most of Australia and do best sown or laid from spring to early autumn, when the soil is warm. Cool-season grasses (tall fescue, ryegrass) suit Tasmania, Canberra and cooler southern areas, and are best sown in autumn or spring. Turf can be laid most of the year in warm areas, but needs much more water in summer.
Topsoil and feed quantities
Topsoil = area × depth, plus about 15% for settling. A cubic metre covers about 10 m² at 100 mm. Feed follows the product's rate. The lawn feed calculator works out how much to buy.
A worked example
A 10 × 8 m lawn (80 m²) in instant turf: 84 m² with 5% extra, about one and a half pallets. Turf underlay soil at 100 mm: 8 m³ plus settling, about 9 m³. A bag of starter fertiliser.
Aftercare to include in the quote
Tell the client how to water, when to first mow (when the grass is about a third longer than mowing height, with the blades set high), and to keep traffic off for the first few weeks. Many callbacks on new lawns come from aftercare, not installation.
The turf calculator and grass seed calculator work out quantities, with topsoil and feed alongside.
Common questions
Can I lay turf or seed on clay?
Yes, but drainage is key. Break up the surface, work in organic matter or coarse washed sand, and add a good layer of topsoil. On very heavy, wet ground, a land drain may be needed first.
What about shady areas?
Choose a shade-tolerant seed mix, and expect a thinner lawn under trees. In deep shade, ground cover plants or mulch often do better than grass.
How long until the client can use it?
Turf can usually take light use after three to four weeks, once it has rooted. Seeded lawns need two to three months, and a full season before heavy use.
This guide is general information for estimating. It is not engineering, legal or tax advice. Check the NCC, Australian Standards and your building surveyor or certifier for your project.