G’day, Nikolai here from The Lawn Firm. If you’re seeing soft, pale-green tufts popping up through winter and early spring, that’s winter grass (Poa annua). I deal with it across Canberra and the ACT every season. Here’s a clear, step-by-step guide to help you stop it spreading and keep your turf thick and clean.

What is winter grass?

Winter grass is a cool-season grassy weed. It grows fast in cold weather, sets seed early, and weakens your lawn. It competes for light, water, and nutrients. Left alone, it spreads and returns each year with a bigger footprint.

ACT quick facts

Season: Late autumn to early spring
Look: Light-green clumps, soft leaves, shallow roots
Seed heads: Small white seed heads that appear low in the canopy
Risk: Rapid re-seeding and a thin, patchy lawn through spring

How I identify winter grass fast

Colour contrast: Lighter green than surrounding grass.
Texture: Soft, fine blades that flatten underfoot.
Seed heads: Tiny white seed heads even at low mowing heights.
Root check: Shallow roots, clumps lift easier than established turf.

Why winter grass thrives in Canberra

Cool soil: Germination starts as soils cool in late autumn.
Compaction: Clay soils restrict turf roots and favour shallow weeds.
Low mowing: Scalping opens space for weeds to colonise.
Thin turf: Bare patches invite winter grass to take hold.

Prevention beats cure (my ACT playbook)

Aerate in autumn: Relieve compaction so your lawn outcompetes weeds.
Fertilise smart: Support steady growth to keep coverage dense.
Raise mowing height: Shade the soil and reduce weed germination.
Overseed thin areas: Fill gaps before winter so weeds can’t move in.
Pre-emergent timing: Apply a seasonally timed barrier in late autumn to block germination.
Hygiene matters: Clean mower decks and shoes after working in infested areas.

Control options once you see it

Hand removal: Best for small patches, lift clumps before seed heads mature.
Targeted treatment: Apply a selective approach suited to grassy weeds (not broadleaf only). Avoid blanket sprays on stressed turf.
Mowing discipline: Don’t scalp. Keep blades sharp and maintain a consistent height so your lawn stays stronger than the weed.
Watering habits: Water deeply and less often. Shallow, frequent watering encourages shallow-rooted weeds.

Recovery after a heavy infestation

Remove seed heads and reduce the seed bank as soon as possible.
Light top dress (5–8 mm) and overseed thin zones to rebuild density.
Core aerate in spring to drive deeper roots and improve resilience.
Follow with a balanced feed to kick on fresh growth and close the canopy.

My Canberra timing guide

Late autumn: Aerate, apply pre-emergent, and fix bare spots.
Winter: Monitor, hand-remove, and keep mowing heights steady.
Early spring: Remove survivors, overseed, light top dress, and feed.
Spring into summer: Strengthen turf so winter grass has fewer entry points next year.

Common mistakes I fix

Treating it like a broadleaf weed: Winter grass is a grassy weed; use the right strategy.
Scalping to “cut it out”: Scalping weakens turf and spreads seed.
Skipping aeration: Compaction invites repeat infestations.
Letting seed set: Seed heads today are next winter’s problem.

DIY or call The Lawn Firm?

You can hand-remove small patches and adjust mowing and watering. For wider infestations, timing and technique matter. I assess the lawn, set the right seasonal plan, and coordinate aeration, fertilising, overseeding, and targeted weed control so winter grass loses its foothold, for good.