By Claire Bickle
Lawn grubs are notorious summer pests that can quickly damage or even destroy a flourishing lawn. What many people don’t realise is that there are two main types of lawn grub that cause most problems. Here’s your guide to tell them apart and what you need to do next!
Identifying lawn grubs
When it comes to lawn grubs, knowing which type you’re dealing with is key to choosing the right control method.
Lawn Armyworm (Spodoptera mauritia)
Armyworms aren’t actual worms at all—they’re the caterpillar (larval) stage of a moth. They march relentlessly across turf under the cover of darkness, devouring blades of grass from the top down until entire patches seem to vanish overnight. Their arrival is often sudden and their appetite voracious, leaving behind brown, chewed swathes of damaged lawn.
White Curl Grubs (Scarab Beetle Larvae)
White curl grubs are the plump, C-shaped larvae of scarab beetles common in Australia, including the African black beetle (Heteronychus arator) and the Argentine scarab (Cyclocephala signaticollis). Hidden in the soil, they feast on grass roots, causing lawns to wilt, yellow and die back in irregular patches. Unlike the armyworm’s dramatic assault, curl grubs cause a slow decline that can be mistaken for water stress or poor nutrition.
Organic control and management of lawn grubs
Managing these pests requires regular lawn inspections and encouraging birds and beneficial insects. If treatment is necessary, choose targeted biological or organic options to protect the health of your garden ecosystem.
Certified organic treatments are critical to protect birdlife and other wildlife from poisoning when they may eat a contaminated grub or caterpillar that is dying on the surface.
Be careful when applying even organic remedies—eliminating white curl grubs can also affect other beneficial beetle species, including our beloved Christmas beetles!
For more information on identifying and treating lawn grubs click here to read an article written by About The Garden.
Lawn grubs and recovery
If your lawn has been affected, top-dress with Rocky Point’s OptiLawn Top Dress to level and stimulate new growth. You may need to re-seed or patch areas with turf. Then apply Rocky Point’s Lawn Food, available in a 2L hose-on pack. This seaweed-enriched fertiliser helps restore vitality and get your lawn back on the road to recovery.
Once recovered, regular applications of Rocky Point’s Lawn Food and OptiLawn Granular Fertiliser throughout summer will keep your lawn in tip-top shape and resilient against future infestations.
