Common Victorian Lawn Pests: What’s eating your turf and how to stop them

Common Victorian Lawn Pests: What's eating your turf and how to stop them

There's nothing quite like walking barefoot across a healthy, green lawn on a warm Victorian evening. But if you've noticed brown patches creeping in, birds pecking relentlessly at the turf, or areas that feel spongy underfoot, there's a good chance something unwelcome has moved in beneath the surface. Lawn pests are one of those challenges that every Victorian homeowner is likely to face at some point, and knowing what to look for can make all the difference between a quick fix and a costly repair.

Here at Coolabah Turf, we've spent years helping families across Victoria grow lawns they're proud of. So we thought we'd walk you through some of the most common culprits that like to call your lawn home, and share a few tips on keeping them under control.

African Black Beetle

The African Black Beetle is one of the most widespread lawn pests across Victoria, and it's the larvae that do the real damage. Adult beetles are shiny, dark brown to black, and roughly 12 to 15 millimetres long. You might spot them wandering across paths or driveways on warm evenings, but it's the curl grubs living beneath your turf that you need to worry about.

These C-shaped grubs feed on the root system of your lawn, severing the grass from its lifeline below the soil. The telltale sign is patches of turf that look drought-stressed even when you've been watering regularly. In more advanced cases, you can actually peel the turf back like a carpet because the roots have been chewed away entirely. If you're noticing magpies, crows, or other birds digging into your lawn with unusual enthusiasm, they're likely feasting on grubs just beneath the surface.

The grub stage is most active through late summer and autumn, which is the ideal window to treat. A quality lawn grub killer applied according to the label directions and watered in thoroughly will usually bring things under control. Prevention is always easier than cure though, so an annual preventative treatment in early summer can save you a lot of heartache down the track.

Lawn Armyworm

If you wake up one morning to find large sections of your lawn looking like they've been mowed down to the soil overnight, there's a strong chance armyworm has paid a visit. These caterpillars are the larvae of a nondescript brown moth, and they tend to appear in large numbers after periods of warm, humid weather, particularly through late spring and summer.

Armyworms feed on the leaf blade of the grass, and because they move in such large groups, they can strip an area bare in a remarkably short time. They tend to feed at night and hide in the thatch layer or just below the soil surface during the day, which is why the damage often seems to appear out of nowhere. A simple test is to mix a bucket of soapy water and pour it over a suspect area. If armyworms are present, they'll wriggle to the surface within a few minutes.

The good news is that armyworm damage, while dramatic looking, is mostly cosmetic. Because they feed on the leaf rather than the root, a healthy lawn will generally recover well with proper watering and a light fertilise once the pest has been dealt with. Treating with an appropriate insecticide in the late afternoon, just before the caterpillars emerge to feed, tends to give the best results.

Couch Mite

Couch mite is a pest that's specific to couch grass varieties, and it can be a real headache for Victorian homeowners who grow couch lawns. These microscopic mites are invisible to the naked eye, but the damage they cause is unmistakable. Infested grass develops a distinctive "witches' broom" appearance, where the nodes become bunched and distorted, creating rosette-like tufts that stand out from the surrounding turf.

Unfortunately, couch mite is one of the more difficult lawn pests to manage because there are limited chemical controls available to home gardeners. Maintaining a vigorous, well-fed lawn is one of the best defences, as healthy turf can better tolerate and outgrow minor infestations. In severe cases, removing and replacing the affected areas may be the most practical solution.

If you're planning a new lawn and couch mite is a concern in your area, it's worth having a chat with our friendly team of turfies about which variety might be the best fit for your situation. Some varieties naturally handle pest pressure better than others, which is something the Coolabah team know lots about!

Scarab Beetle Grubs (Including Argentine Scarab)

While the African Black Beetle gets most of the attention, Victoria is home to several other scarab beetle species whose larvae behave in much the same way. The Argentine Scarab is one that's become increasingly common in parts of Melbourne and regional Victoria in recent years.

Like their African Black Beetle cousins, these grubs live in the soil and feed on grass roots. The symptoms are largely the same: browning patches, spongy turf, and an unusual amount of bird activity on the lawn. The key difference is that Argentine Scarab grubs tend to be slightly smaller and can sometimes appear in even greater numbers, which means the damage can escalate quickly if left unchecked.

Treatment follows the same approach as for African Black Beetle larvae. A targeted grub treatment applied during the active larval stage and watered into the soil will help bring populations down. Keeping your lawn healthy with regular feeding and proper mowing height also gives it a much better chance of bouncing back from any root damage.

Billbug

Billbugs are a lesser-known pest in Victoria, but they can cause significant damage, particularly in buffalo and kikuyu lawns. The adults are small, dark weevils with a distinctive long snout, and they tend to go unnoticed because of their size. It's the larvae, small creamy-white grubs that feed inside the grass stems and crown, that cause the visible damage.

Billbug damage often mimics the look of drought stress or nutrient deficiency, which means it can go undiagnosed for some time. A useful clue is to tug on a brown stem of grass. If it breaks away easily at the crown and you can see frass (a fine, sawdust-like material) inside the stem, billbug is likely responsible.

Because the larvae feed inside the plant rather than on the roots, they can be harder to reach with conventional surface-applied treatments. Systemic insecticides tend to be more effective, and timing the application to target young larvae before they've caused extensive damage is important.

Two-Spotted Mite

Also known as red spider mite, the two-spotted mite is a pest that becomes particularly troublesome during hot, dry conditions, much like the summer we have just experienced in Victoria! These tiny mites feed by piercing individual grass cells and sucking out the contents, which gives the lawn a silvery, bleached appearance. In heavy infestations, you might also notice fine webbing across the turf surface, particularly in areas that are sheltered from wind.

Two-spotted mite thrives when lawns are under stress from heat and lack of moisture, so one of the simplest and most effective management strategies is to maintain a consistent watering schedule during the warmer months. A deep, thorough watering a few times a week is far more beneficial than light daily sprinkles, as it encourages deeper root growth and a more resilient lawn overall.

If mite pressure is high, a targeted miticide can help bring numbers down, but improving the growing conditions for your lawn should always be the first step.

When to Call in Professional Help

Most lawn pest issues can be managed effectively at home with the right products and a bit of know-how. But if you're dealing with persistent problems, widespread damage, or you're just not sure what's going on, it's always worth reaching out to a turf professional or your local garden centre for advice.

Here at Coolabah Turf, we're always happy to help you work through any lawn challenges you might be facing. Whether you're looking to repair a pest-damaged area with fresh turf or simply want some guidance on keeping your lawn in top shape through every season, our team is just a phone call away. We have a full range of aftercare products available online, and our Lawn Doctor service is just part of the Coolabah promise.

Keeping Your Victorian Lawn Healthy and Pest-Free

At the end of the day, the best defence against lawn pests is a healthy, well-maintained lawn. Regular mowing at the right height, consistent watering, seasonal fertilising, and keeping an eye out for early warning signs will go a long way toward preventing pest problems before they take hold.

Victoria's climate means we get our fair share of pest activity, but with a little attention and care, there's no reason your lawn can't stay thick, green, and looking its best all year round. And if you ever need a hand, the Coolabah Turf team is right here in your corner.