Winter grass (Poa annua) is a common and persistent weed in lawns, particularly in cooler climates. It thrives in the winter and early spring, producing large quantities of seed that can quickly spread throughout your lawn. Preventing and treating winter grass involves a combination of cultural practices and targeted treatments. Here are some strategies to help you manage this weed effectively.
Regular Mowing: Keep your grass at the recommended height for its type. A healthy, dense lawn can outcompete most weeds. Raising your mower height slightly can help your lawn grass shade out winter grass seedlings.
Proper Watering: Water deeply but infrequently to encourage deep root growth. Avoid overwatering, Winter grass does best in moist conditions.
Fertilisation: Apply a balanced fertiliser following your grass type’s needs. Healthy grass is more competitive against weeds.
Aeration: Aerate your lawn to reduce compaction and improve drainage. Well-aerated soil is less favourable for winter grass.
Mulching: Use mulch in garden beds to prevent weed seeds from germinating.
Edging: Install physical barriers between your lawn and garden beds to prevent the spread of winter grass.
Hand Weeding: For small infestations, manually pull out winter grass before it seeds. Ensure you remove the entire root system to prevent regrowth. Regularly check your lawn and remove any new winter grass plants.
Pre-emergent Herbicides: Apply a pre-emergent herbicide in late summer to early autumn before the seeds germinate. We stock a range of pre-emergent herbicides and recommend either David Greys winter grass killer or LSA’s Oxafert pre-emergent to stop winter grass before it can even appear.
Post-emergent Herbicides: If winter grass is already growing, use a selective post-emergent herbicide that targets Poa annua without harming your lawn grass. Glyphosate can be used in severe cases but will kill any grass it contacts, so apply it carefully.
Preventing and treating winter grass is easiest when integrating multiple different methods, including factoring it into your regular lawncare routine. Monitoring growth , manual removal, and strategic use of herbicides. By integrating these methods, you can keep winter grass under control and enjoy a lush, healthy lawn year-round.