When and Why to Aerate and Overseed Your Lawn

Aeration and overseeding work together to restore a thin, compacted lawn by opening the soil and then filling it with new, resilient grass plants. Done at the right time in Saskatoon’s climate, they can dramatically improve density, color, and overall lawn health.

What aeration does for your lawn

• Core aeration pulls small plugs of soil from the lawn, easing compaction so air, water, and nutrients can move more freely down into the root zone.

• By opening the surface, aeration also helps reduce thatch buildup, improves drainage, and creates conditions that are less favorable for certain lawn diseases.

Best timing in Saskatoon

• Early fall—roughly September to mid‑October—is usually the “sweet spot” for aeration and overseeding because the soil is still warm enough for seed to germinate, while cooler air temperatures reduce stress on new grass.

• Late spring can also be a good window if you are repairing winter damage and bare patches, especially once the lawn is actively growing and the soil is no longer saturated.

Why overseeding matters

• When you overseed immediately after aeration, a portion of the seed drops into the core holes, where it is better protected from birds, wind, and foot traffic and has good contact with soil.

• Choosing a high‑quality cool‑season grass blend designed for Western Canadian conditions improves drought tolerance, wear resistance, and overall durability, helping your renovated lawn stay thicker and greener for the long term.