Vertimowing and dethatching in Perth

Thatch is the layer of dead and living stems, runners and roots that builds up between the green growth on top and the soil underneath. A thin layer is normal and even useful — it cushions the lawn. Once it gets thick, it turns into a mat that behaves like a sponge sitting on top of your soil.

That mat is the problem. Water hits it, spreads sideways through it and evaporates before it ever reaches the soil. Fertiliser does the same. The grass responds by rooting into the thatch itself rather than into the ground, which leaves it with no drought reserve at all — so the lawn browns off in the first hot week and never quite recovers.

Perth's most common lawn types are the ones most prone to it. Kikuyu and couch are vigorous runner grasses that build thatch quickly, especially when they're well fed and well watered. Buffalo builds a coarser thatch more slowly but builds it. Add a long growing season and years of regular watering, and a thick thatch layer is close to the default state of an established Perth lawn that has never been renovated.

This is why so many people conclude their lawn is beyond help after a couple of seasons of feeding and watering harder. They're feeding and watering a sponge.

Timing matters more for this job than for anything else we do, because vertimowing deliberately takes the lawn back hard. It has to be done when the grass is growing strongly enough to recover and fill back in, which for warm-season grasses means spring through to early summer once the soil has properly warmed.

Early autumn can work while there's still real warmth in the ground. Mid-winter is the wrong time: a warm-season lawn taken back in July will sit there thin and open, and weeds will get the space before the grass does. Peak heat is also poor timing if the lawn is already stressed.

Once every year or two is right for most lawns, depending on how fast yours builds thatch. Vigorous, well-fed kikuyu might want it annually; a slower buffalo lawn might go two or three years.

Vertimowing is available right across Perth south of the river, from North Fremantle across to Belmont, out to Byford and south to Mandurah. Full list on the service areas page.

The lawns that need it most are the established ones — decades of kikuyu and couch growth on the mature streets of Spearwood and Bibra Lake, and the older parts of the Fremantle flank. Newer turf around Cockburn Central is usually a few years off needing it, and those lawns tend to want aeration first.