The right mowing height for Melbourne lawns, by species
By Tim Le Grand, owner-operator · Published 24 September 2026
A steady height and regular light cuts keep a commercial lawn dense through the growing season.
The short answer. Kikuyu and couch are happiest cut between 25 and 50 mm, buffalo between 40 and 60 mm, and tall fescue blends between 50 and 75 mm. The bigger rule sits above all of those numbers. Never remove more than a third of the leaf in one cut. Most turf problems on managed sites trace back to breaking that rule, not to the height setting itself.
Why height matters more than it looks
Leaf length and root depth are linked. Turf cut very short carries shallow roots, dries out faster, and opens gaps that weeds fill. Turf held a little longer shades its own soil, holds moisture through summer and crowds weeds out. On a commercial water bill across a large site, a sensible mowing height is a cost decision, not just a cosmetic one.
Heights by species
Kikuyu is the workhorse of Melbourne common areas and takes 25 to 50 mm comfortably, sitting toward the top of that range in summer. Couch can be cut lower than most grasses and looks its best around 25 to 40 mm on a well maintained surface. Buffalo holds its colour and softness at 40 to 60 mm and resents being cut low, thinning quickly if it is. Cool season tall fescue and rye blends want 50 to 75 mm and should never be shaved, especially heading into summer.
Shaded areas of any species should run 10 to 15 mm higher than the open lawn around them, because leaf is how grass makes up for missing light.
Tall fescue is the one that punishes a mistake. On a fescue lawn I manage, January and February are make or break, and the plan for those months is simple. Lift the height and keep the water up to carry it through the heat.
The one third rule
Removing more than a third of the leaf in a single cut shocks the plant, browns the surface and stops root growth while the grass recovers. This is why a fortnightly schedule that stretches to four weeks in spring produces a scalped, straw coloured lawn. The height setting did not change, but the amount removed did. Frequency and height work as a pair. If visits move further apart in winter, height should ease up with them.
A fixed day helps more than people expect. On one body corporate site I found a car parked on the lawn. I photographed it for the file, and the fixed fortnightly cadence means residents now know which day to move their cars, so the whole lawn gets the same cut every visit.
Sharp blades matter as much as height
I will admit I learned this one the hard way. A blunt blade does not cut grass, it tears it, about as well as a butter knife would, and the torn tips brown off within days. Blade maintenance is now booked as a job in my own schedule, at my own address, so it happens on time rather than when I remember.
Earlier this year I also standardised the cutting heights across my mowers, with the deck rake set through the levelling adjusters at each service, so a site gets the same cut from one visit to the next.
Seasonal adjustments
Run the same species toward the top of its range through summer, where the extra leaf shades soil and buffers heat. Autumn is the time to bring height gradually back down, never in one cut. Through winter, warm season grasses barely grow and mostly need tidying rather than cutting, while cool season lawns keep growing and keep their normal height. Lifting height by around 25 percent before a heatwave is one of the cheapest protections a site has.
Wet ground needs its own rule. On one site the owner asked me to stay off a soft patch until the grass recovered, and that exclusion went onto the site card, so it is respected whichever day I visit.
Scalping, and what it costs
Scalped turf photographs badly, but the real cost arrives later. Thin cover lets summer weeds establish, shallow roots push watering demand up, and repairs land on next year's budget. On commercial frontages and common areas, holding a disciplined height and frequency through the growth months is what keeps a site looking managed between visits, and it is a fair thing to specify in a maintenance agreement in millimetres rather than adjectives.
Mowing height questions
Can kikuyu be cut really short to slow it down?
Cutting short does not slow kikuyu, it just stresses it and invites weeds while the runners keep spreading. Frequency is the honest way to manage kikuyu vigour through spring and summer.
Why does our shaded lawn keep thinning?
Shade lawns need more leaf to survive on less light. Raise the height 10 to 15 mm over the open areas, reduce traffic where possible, and accept that deep shade may suit garden bed planting better than turf.
Does leaving clippings on the lawn help or hurt?
On a frequent schedule where cuts are light, fine clippings return nutrients and are fine. Clumps left after a long gap smother grass and should be caught or cleared.
