What's Happening to Your Perth Lawn This Winter and What to Do About It

Your lawn looked great in March. Now it's May, the temperatures have dropped, and something has clearly changed. The colour is fading, a patch has appeared near the back fence, and weeds are creeping in from the edges. Sound familiar?

Most of what you're seeing is completely normal. Perth winters are mild by national standards, but they still trigger real changes in warm-season turf. Knowing what's normal versus what needs attention is the difference between a lawn that bounces back beautifully in spring and one that doesn't. As the weather cools, it's the perfect time to get your lawn winter-ready. Winter lawn care in Perth doesn't need to be complicated. Here's what's happening and exactly what your turf needs right now.

As Perth's cooler months arrive, our greenkeepers are out making sure every lawn is ready for winter.

Why is my Perth lawn changing colour?

Sir Walter Buffalo, Kikuyu, and Wintergreen Couch are all warm-season grasses. As soil temperatures drop and daylight hours shorten, they naturally slow their growth and begin to lose their deep green colour. This is called dormancy, and it's a completely normal survival response.

Uniform fading across the whole lawn is dormancy. Circular or irregular patches, areas that appear suddenly, or spots with defined dark edges are a different story and worth a professional assessment. If you're unsure, our greenkeepers are available for phone advice between visits or you can book an in-person consultation.

Should I fertilise my lawn before winter?

Yes, and now is the right time. Applying a slow-release fertiliser heading into winter is one of the most important things you can do for your turf. A formula high in potassium strengthens the cell wall, improves disease resistance, and helps your lawn handle the stress of cold and wet conditions.

Heavy nitrogen applications in winter push soft growth the plant can't sustain and increase the risk of fungal disease. Our Bio-Stimulating Fertilisers are specifically formulated for Perth's free-draining sandy soils, keeping nutrients where the roots need them rather than leaching straight through the profile.

Homeowners across South Perth, Dalkeith, Applecross, and the Perth Hills consistently see better spring recovery from lawns that receive the right winter nutrition.

Should I aerate before winter?

Absolutely. Perth's winter rain saturates our sandy soils and if there's any compaction, that water sits on the surface rather than draining through to the root zone. Aeration opens up the soil profile, improves drainage, and gets oxygen back down to the roots. It directly reduces the risk of waterlogging and fungal disease through the wet months.

It's also lower stress for the turf than aerating in summer, when the lawn is under heat pressure and needs maximum leaf coverage.

How do I get on top of weeds this winter?

While your grass slows down, the weeds don't. Bindii, winter grass, clover, and oxalis all thrive in cooler, wetter conditions and they exploit any weakness in your turf. The most effective approach is pre-emergent weed control applied before they establish, rather than trying to remove them once they've taken hold.

Pre-emergent products prevent germination rather than killing established weeds. Our pre-emergent treatments are exempt from poison scheduling, meaning they're safe for kids, pets, and the environment. If bindii or broadleaf weeds are already present across your lawn in suburbs like Fremantle, Joondalup, or Mandurah, a targeted selective post-emergent is the right next step.

What about watering and mowing in winter?

Scale back watering but keep it consistent. Perth's Water Corporation regulations prohibit residential reticulation from 1 June through 31 August. Perth's winter rainfall is sufficient for established lawns. Turn your system off, check the controller is set correctly, and use the winter months to service your reticulation so it's ready for spring. If a dry spell hits and your lawn looks stressed, hand watering is permitted.

On mowing, raise your cutting height slightly to protect against cold nights. Extra leaf surface helps the plant capture limited winter sunlight and reduces vulnerability at the crown. Reduce frequency to once every two to three weeks, and never scalp a dormant lawn.

Your winter lawn care Perth checklist

As a summary, here is what your turf needs right now:

✅ Fertilise with a slow-release formula heading into winter

✅ Aerate compacted soil so water and nutrients can reach the roots

✅ Control weeds pre-emergently before they establish

✅ Scale back watering but keep it consistent

✅ Raise your mowing height slightly to protect against cold nights

Positively Green services lawns across Perth metro from Two Rocks and Yanchep in the north to Mandurah in the south, including the Perth Hills and monthly visits to Bunbury and Margaret River. Our greenkeepers bring 40 years of professional turf management experience to every visit.

👉 Last years blog on Autumn Lawn Care: Preparing Your Lawn for the Cooler Months

👉 Explore our Lawn Care Plans

👉 Book a Reticulation Health Check