It's mid-May. The mornings are cold, the growth has slowed, and your mower is collecting dust in the shed. You're thinking: leave it until September.
That instinct will cost you. What you do in the next six weeks decides whether your lawn bounces back fast in spring or spends October looking patchy while your neighbour's is already green.
I run Sir Walter Buffalo on heavy clay in Ipswich, but I've helped mates with Couch, Kikuyu, and Zoysia lawns across SEQ. Here's what each species needs right now — find yours and get the timing right.
The universal rules (every grass type)
Before we get into specifics, these apply to everything growing in Australian soil right now:
Raise the mowing height. Whatever you're cutting at, go up one notch. Taller leaf blade means more photosynthesis during shorter days, and better insulation against frost. Don't scalp going into winter — that's a spring move.
Last fertiliser feed by end of May. Warm-season grasses are about to go semi-dormant. Feeding them in June pushes soft growth that's frost-tender. Get your final autumn feed done now — a slow-release or potassium-heavy blend, not high nitrogen.
Back off the watering. Evaporation has halved since February. Most lawns in most regions can go to once a week or less. Overwatering in cool weather is the fastest path to fungal disease.
Watch for winter weeds. Wintergrass (Poa annua), bindii, clover, and cudweed germinate now while your lawn is slowing down. Pre-emergent should already be down. If it's not, you're doing post-emergent spot spraying from here.
Buffalo (Sir Walter, Palmetto, Sapphire, DNA Certified)
Buffalo is the most popular warm-season turf in Australia, and for good reason — it handles shade, looks good year-round in most climates, and doesn't go fully dormant in winter like Couch does.
Mowing: Raise to 50–65mm. Buffalo stores energy in its leaf, so cutting too low going into winter weakens it. I keep mine at 60mm from May through August. Mow less frequently — fortnightly or even every three weeks as growth stalls.
Fertilising: Last feed now with a slow-release fertiliser. Use a potassium-heavy autumn/winter blend (look for a ratio where K is higher than N, like 10-5-15 or a dedicated winteriser). Potassium helps cold tolerance. Avoid high nitrogen — you'll push soft top growth that gets hammered by frost.
Watering: Once a week maximum in most regions. In SEQ I'm down to every 10 days. If you're getting regular rain, turn it off entirely. Buffalo's root system is deep enough to handle dry spells in cool weather.
Weeds: Buffalo is sensitive to many broadleaf herbicides — never use dicamba on Buffalo (avoid products like Contra M or Kamba M). For broadleaf weeds, use a product specifically formulated for Buffalo — Bow & Arrow (MCPA + clopyralid + diflufenican) is safe on most modern cultivars like Sir Walter and Palmetto. Note: while Bow & Arrow contains MCPA, it's formulated at Buffalo-safe concentrations — pure high-strength MCPA products (like MCPA 750) will damage Buffalo. Always check the label for your cultivar. For wintergrass, you needed pre-emergent in March. If it's already up, professional-grade options like Endothal (Poachek) or Ethofumesate (Tramat) can treat Poa in Buffalo — consult a turf professional for rates.
Disease: Grey leaf spot drops off in winter, but you might see Rhizoctonia patch (sometimes called large patch) in cool, damp conditions. It shows as circular brown areas, often at the edges of the lawn. Improve airflow, reduce watering, and apply a contact fungicide if patches appear. LawnSuite's AI diagnosis can confirm what you're seeing from a photo before you spray.
The one thing people forget: Autumn (March–May) is actually the ideal time to aerate warm-season lawns — it relieves summer compaction and improves drainage before winter rain. Don't confuse aeration with dethatching — dethatching is far more invasive and should wait until late spring when the grass is actively growing.
Couch (Bermuda, TifTuf, Wintergreen, Legend)
Couch is the grass that goes properly dormant. By June in southern states, it'll be straw-coloured and looking dead. It's not dead — it's sleeping. The mistake is panicking and overwatering or fertilising a sleeping lawn.
Mowing: Raise to 25–35mm. Couch can handle lower cuts than Buffalo, but still raise it for winter. Once it goes dormant, stop mowing. There's nothing to cut.
Fertilising: Last feed by mid-May, ideally with a potassium-focused blend. Some people do a final hit of iron sulphate to maintain colour as long as possible — 2–3g/m² dissolved in water, applied in cool conditions (avoid hot days to prevent scorch). It doesn't prevent dormancy, but it keeps the green a few weeks longer.
Watering: Minimal. In Melbourne and Adelaide, winter rain is more than enough. In Brisbane and Sydney, once every two weeks at most. A dormant Couch lawn needs almost no water.
Weeds: This is Couch's biggest winter weakness. When it goes dormant, the bare patches become weed highways. Pre-emergent herbicide (prodiamine-based products like Spartan) in March/April was critical. If wintergrass is already up, propyzamide-based products (check your local garden centre for wintergrass killers labelled for Couch) can work as a post-emergent — but always check the label for your cultivar. Bindii can be treated with selective broadleaf herbicides labelled for Couch.
Oversowing with ryegrass: Some Couch owners oversow with annual ryegrass in late April to keep the lawn green through winter. It works — but the ryegrass competes with the Couch in spring and needs to be scalped out. I stopped doing it. I'd rather have a brown lawn for three months than spend October fighting ryegrass.
Disease: Minimal in winter. Couch's dormancy is actually protective. Spring dollar spot is more of a concern — keep an eye out from September.
Kikuyu
Kikuyu is the tank of Australian lawns. It grows faster than everything, stays greener longer into autumn, and recovers from basically anything. Its winter challenge isn't survival — it's staying manageable.
Mowing: Raise to 40–60mm and keep mowing. Kikuyu doesn't go fully dormant in most of Australia. Even in Melbourne it'll push some growth through winter. The extra leaf height helps photosynthesis during shorter days. Mow every 2–3 weeks to prevent thatch buildup.
Fertilising: Last feed now. Kikuyu is a nitrogen hog, but don't feed it in winter or you'll be mowing in July when you'd rather be inside. A balanced slow-release is fine. Some people skip the autumn feed entirely — Kikuyu will survive either way.
Watering: Barely any. Kikuyu's root system is incredibly deep. In most regions, rainfall is sufficient through winter. Only water if you've had two weeks without rain and the lawn is looking stressed (leaf curl, blue-grey tinge).
Weeds: Kikuyu is so aggressive it usually outcompetes weeds. But in winter when it slows down, bindii and clover can sneak in. Kikuyu is tolerant of most broadleaf herbicides including MCPA, dicamba, and products like Bow & Arrow — unlike sensitive Buffalo. Always use a product labelled for your turf type and follow current regulations.
Thatch: If your Kikuyu is spongy underfoot, don't dethatch now — late autumn doesn't give the lawn enough growing time to recover before winter. Wait until late spring (October–November) when Kikuyu is in full growth mode and can fill in quickly. Light raking is fine, but heavy scarifying should wait.
The Kikuyu invasion problem: If your Kikuyu is creeping into garden beds, now is actually a good time to edge hard. Growth is slow enough that a clean cut edge will hold for a few months.
Zoysia (Empire, Nara, Palisades, Zoysia Australis)
Zoysia is the slow-and-steady grass. It grows slowly, goes dormant slowly, and recovers slowly. That means your winter prep window is longer, but mistakes take longer to fix.
Mowing: Raise to 30–45mm. Zoysia's fine leaf looks best at lower heights, but going into winter, give it the extra length. Mow frequency drops to every 3–4 weeks.
Fertilising: Last feed now. Zoysia doesn't need much fertiliser generally — half the rate you'd use on Couch. A slow-release with potassium is ideal. Over-fertilising Zoysia leads to thatch problems, and thatch in winter leads to disease.
Watering: Very little. Zoysia is extremely drought tolerant. In most regions, winter rainfall is more than enough. In Perth and Adelaide, you might water once a fortnight if there's no rain.
Weeds: Zoysia's dense growth habit is its best weed defence, but winter thinning can let weeds in. Pre-emergent is important. Post-emergent broadleaf herbicides are generally safe on Zoysia — check your cultivar, but most handle MCPA, bromoxynil, and dicamba.
Disease: Large patch (Rhizoctonia) is the main winter/spring concern for Zoysia. It shows up as circular brown patches in cool, humid conditions. Reduce watering, improve drainage, and treat with a systemic fungicide if needed. Get a diagnosis before spraying — LawnSuite's photo diagnosis can distinguish large patch from dormancy discolouration.
Cool-season grasses (Ryegrass, Tall Fescue, Kentucky Bluegrass)
If you're in Melbourne, Hobart, Canberra, or the Southern Highlands and you're growing cool-season turf — congratulations, this is your lawn's best season.
Mowing: Maintain at 50–75mm. Cool-season grasses are actively growing through autumn and winter. Keep mowing regularly — every 7–10 days depending on growth.
Fertilising: Feed now and again in mid-winter (July). Cool-season grasses are the opposite of warm-season — they want nutrition through the cool months. A balanced NPK fertiliser every 6–8 weeks is ideal.
Watering: Water as needed. Cool-season grasses don't have the deep root systems of Couch or Kikuyu. They'll show drought stress faster, even in winter. Keep the soil moist but not waterlogged.
Weeds: Fewer weed problems in winter because your grass is actively growing and outcompeting. Spot-spray any broadleaf weeds as they appear.
Oversowing: Late autumn (right now) is the perfect time to oversow thin patches. Soil temperatures are ideal for ryegrass and fescue germination. Lightly rake bare spots, spread seed, top-dress with fine soil, and keep moist.
Disease: Snow mould and fusarium patch can appear in very cold, wet conditions. Ensure good drainage and avoid heavy nitrogen in late autumn.
The month-by-month cheat sheet
| Task | May | June | July | August |
|---|---|---|---|---|
| Mowing | Raise height, slow frequency | Minimal (warm-season) / Regular (cool-season) | Same | Start watching for spring growth |
| Fertilising | Last autumn feed (warm-season) | None (warm-season) / Feed (cool-season) | Feed cool-season | Pre-spring feed late August |
| Watering | Reduce to weekly | Rainfall only (most regions) | Same | Same |
| Weeds | Post-emergent spot spray | Hand-pull wintergrass | Monitor bindii | Pre-emergent for spring weeds |
| Disease | Watch for brown patch | Monitor damp areas | Minimal | Watch for dollar spot |
Track it, don't guess
The biggest mistake I made in my first year was doing everything from memory. I'd fertilise, forget when I did it, then fertilise again three weeks later. I'd see a brown patch and spray fungicide when it was actually just dry.
Now I log everything in LawnSuite — treatments, mowing dates, watering events, even photos of problem spots. When something goes wrong in spring, I can look back and see exactly what I did (or didn't do) in autumn.
The AI diagnosis feature is genuinely useful this time of year. Brown patches in winter could be dormancy, drought stress, fungal disease, or dog urine. A photo takes three seconds and the AI tells you which one it is before you waste money on the wrong product.
Try it free — no install, works in your browser.
Written from Ipswich, QLD on a cold May morning, staring at a lawn that's still mostly green because I did my autumn prep two weeks ago. If you're reading this in June, you're not too late — but you're close.
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