There's no single answer to "how often" because it depends on your grass and the season. But there's a sensible default that works for most Coast lawns — fortnightly through the growing season, monthly once things slow down.
From September through May, couch and kikuyu push hard. If you stretch beyond two weeks, you end up taking more off in one cut than the rule of one-third allows, and the lawn yellows for a fortnight afterwards. Fortnightly keeps it tidy and keeps the colour.
Through winter (Jun–Aug) the growth eases off. Most lawns can sit at three to four weeks between cuts. Wet patches and shaded sections might still need a tidy more often.
Buffalo lawns like Sir Walter are slower than couch but want a higher cut. We sit the deck at 40–50mm on buffalo and around 25mm on a tightly-knit couch.
If your lawn has thinned out, the answer is usually "mow more often, at a higher height" — not less often. Frequent, shallow cuts thicken a lawn faster than letting it grow tall and then taking the lot off.
Not sure which schedule fits? Send us a photo and an address, and we'll quote a cadence to match. No upselling — if monthly is enough, we'll say so.