Aeration & Overseeding

Why compaction is Seattle's quiet lawn killer

Much of the soil under Seattle lawns is glacial till, dense clay compacted over thousands of years and further packed down by decades of foot traffic, parked cars, and construction. That compaction means water pools on the surface instead of soaking in, roots stay shallow because they can't push through hardpan, and oxygen struggles to reach the root zone at all. The visible result is usually one or more of the same handful of symptoms: standing water after rain, thinning grass in high-traffic areas, and lawns that never seem to fully green up even with regular fertilization.

Core aeration is the most direct fix. Our equipment pulls actual plugs of soil out of the lawn, rather than just poking holes with solid spikes, which is the difference between meaningfully relieving compaction and barely touching it. Those plugs are left on the surface to break down naturally, returning organic matter to the lawn while the holes they leave behind let water, air, and nutrients reach root systems that have been starved of all three.

Why we pair aeration with overseeding

Aerating alone opens up the soil, but it doesn't do anything to fill in bare or thinning patches. Right after aeration is also the ideal moment to overseed, because grass seed makes direct contact with soil through the aeration holes instead of sitting on top of thatch where it's unlikely to germinate. We use seed blends selected specifically for Pacific Northwest conditions, typically a mix of fine fescue and shade-tolerant ryegrass varieties bred to hold color and density under the partial shade so common in neighborhoods with mature street trees and backyard conifers.

Fall is generally the strongest window for aeration and overseeding in this region, since cooler temperatures and consistent rain give new seed the best germination conditions without the stress of our dry summer months. A lighter spring aeration is also an option for lawns with heavy compaction or standing water issues that shouldn't wait until fall.

What's included in every visit

• Full-lawn core aeration with commercial equipment
• Overseeding with a Pacific Northwest shade-tolerant seed blend
• Starter fertilizer application to support germination
• Post-visit watering guidance for the following two to three weeks