3 Easy Ways to Know Exactly When to Start Mowing Your Lawn This Spring

As autumn settles across Australia in late March, the lawn care schedule requires some adjustments. Grass growth slows, soil temperatures drop, and the constant mowing of summer eases. Knowing when to make that last cut before winter, and reading your lawn's signals as the season shifts, will ensure your lawn recovers beautifully next spring. The timing depends on understanding what your grass is telling you.

The three methods below offer reliable ways to read those signals, so there's no guesswork needed. Whether you're caring for a buffalo grass backyard in Melbourne or a couch grass lawn in Brisbane, these tips will work with your local conditions. While you're at it, check your mower, as the last cuts of the season require a sharp blade.

Why mowing timing matters more than most gardeners realise

Mowing at the wrong time—too early in spring or too late into autumn—stresses the grass. Cutting too soon after a dry spell risks exposing soil to wind and sun, which can invite weeds. Cutting too late in autumn leaves long grass sitting under morning dew, creating conditions for fungal disease over winter. The three methods below offer different approaches: soil temperature, visual growth rate, and the blade-pinch test. Together, they give you a reliable picture.

Method 1: Read the soil temperature

Grass grows based on the soil temperature. Soil temperature is the most reliable indicator of active grass growth, often used by professional turf managers at sports grounds and golf courses.

For warm-season grasses—couch, buffalo, kikuyu, and zoysia—growth requires a consistent soil temperature of at least 15–18°C at a depth of 10 cm. Below that, the grass slows toward dormancy, and mowing becomes more damaging. Above it, regular cutting encourages denser growth and a stronger root system as it gets cooler.

Use a soil thermometer (available at most hardware stores for around AUD $15–$35) in your lawn in the morning, when readings are most accurate. Take readings across three or four spots, especially shady corners where temperatures are lower. If the average reading is above 16°C, the grass is growing and mowing is a good idea. If readings are between 12–15°C, mow only if the grass has grown beyond its target height. Below 12°C, avoid mowing.

In late March across southern Australia—Melbourne, Canberra, Adelaide—soil temperatures drop from their summer peaks, often staying in the transitional 14–18°C range through April. In Queensland and the Northern Territory, soil stays warmer into May, extending the mowing season. This regional variation is why a thermometer is better than generic advice.

Method 2: Track the visual growth rate

This method needs only a ruler and a notebook, or a weekly photo taken from the same spot. Measure your lawn's growth rate over a week.

Mark a small section of your lawn and measure the height of several grass blades at the start of the week. Measure again seven days later. If your lawn has grown less than 10 mm that week, mowing will cause harm, diverting energy from root development. If it has grown more than 15–20 mm, mowing is overdue.

The one-third rule applies here: never remove more than one-third of the grass blade length in a single cut. If your couch lawn has grown to 45 mm, cut to 30 mm—no lower. Cutting deeper weakens the plant, exposes the lower stem, and slows recovery, especially as autumn temperatures reduce the plant's capacity to recover.

Track this weekly growth measurement over two to three weeks. You'll see the pattern: growth is either consistent and vigorous (requiring mowing), slowing (suggesting less frequent cuts), or stalled (meaning dormancy is approaching and mowing should stop).

Method 3: The blade-pinch test

This method requires just your fingers. It takes under a minute.

Kneel on the lawn and pinch a grass blade between your thumb and forefinger, then pull upwards. Pay attention to the blade's resistance and feel. An actively growing blade will feel firm and waxy, with resistance. The green is vivid, the tip is clean, and there's moisture to the texture. This grass will respond well to cutting.

A blade entering stress or early dormancy pulls away easily, feels limp or papery, or shows a yellowish tinge at the base. Cutting grass in this state removes leaf area the plant cannot replace, making the lawn look worse. If more than a third of your sample pinches reveal this texture, don't mow.

You'll often find different parts of the same lawn behaving differently during autumn. A north-facing slope catches more sun and stays warmer; a shaded section near a fence is moving toward dormancy. The pinch test lets you make distinctions metre by metre.

The professional's approach

The best approach is to combine all three methods. Check the soil temperature on a Monday morning, measure growth rate mid-week, and do the blade-pinch test before mowing. If two of the three indicate active grass growth, mow. If two indicate slowing or stress, wait a week and check again. In autumn, patience can produce better lawns the following spring—the root system is deeper and denser.

Blade height and mower settings for autumn cuts

Raise the mowing height slightly compared to your summer setting, leaving slightly more leaf area—typically 10–15 mm higher than your standard cutting height. For a standard buffalo lawn mowed at 30–35 mm in summer, finish the season at 40–45 mm. For couch, move from a summer height of 20–25 mm to a finishing height of around 30 mm.

Make sure the mower blade is sharp before each autumn cut to avoid damaging the grass. Sharpening or replacing a standard rotary mower blade costs between AUD $10–$45.

Estimated cost overview

Estimated costs (indicative prices, variable by region and retailer)

Frequently Asked Questions