Mountlake Terrace is mid-century houses on city lots, with newer buildings near the transit line. The slopes are gentle, the soils are compacted, and the yards were not designed for the amount of roof water a remodels-worth of downspouts can dump. Small city lawns get mowed short, stay damp, and grow moss in the corners the sun misses. The mat is usually worse than the compaction under it.
Snohomish County · ZIP 98043 · 2020 population 21,272
A thin lawn over a thick mat
We can dethatch a fenced backyard with a walk-behind if the gate is wide enough. The corners by the fence and under the deck stairs are hand work. That is where the moss is deepest and the machine cannot turn.
City lawns often have a buried edge of plastic or a root from the parking-strip tree. We stop when we hit it. After the mat is gone, the lawn looks worse for a week. That is honest. Seed and a slightly higher mowing height are what keep it from returning by November.
The ground in Mountlake Terrace
Lots are modest. A patio, a small lawn, a side yard that has become a moss strip, and a fence that is older than the owners. That is the usual visit. The soil has been walked on for sixty years. Aeration and dethatching change the lawn more than a bag of seed thrown on top.
Where the lot tips, it tips a little, and a low wall or a re-graded swale is enough. We are not cutting roads into a mountain. Pavers get people off the mud by the back door, and a pressure wash takes the black film off a walk that has not seen sun all winter. Plantings should stay in scale with the house. A hedgerow that needs a lift every year is the wrong tree for a forty-foot lot.
How we do the work
Thatch here is usually moss plus a layer of dead stems, not the classic Midwest straw mat. A power rake set too deep tears out the live grass and leaves a scar. We set the blades to lift the mat and stop when we are in soil.
The debris has to leave the property. A thatch layer raked into the bed or left in windrows just moves the problem. We haul it. If the lawn underneath is mostly dirt and shade, dethatching is the start of a different plan, not a greener lawn by itself.
What we look at first
- How thick the moss mat is
- Whether live grass is under it or the mat is the whole lawn
- Irrigation and mowing height that are growing the thatch back
- A place to stage the trailer so we are not blocking a tight drive
Mowing height afterward
Cutting to the dirt is how the mat comes back. We leave the grass taller than a golf collar, especially in shade. Tall enough to shade its own soil, short enough to walk.
Pairing it with aeration
On clay and fill we dethatch and then core, in that order. Cores through a mat waste the tines. Seed goes into the opened ground the same day when the season allows.
How deep we go
Shallow enough to save the crowns of the grass. If the lawn is thin, a second light pass beats one aggressive pass that pulls the plants out by the roots. You should see soil in places and live grass still standing.
More from this crew
- Lawn dethatching across Snohomish County
- Lawn aeration in Mountlake Terrace
- Lawn seeding in Mountlake Terrace
- Lawn mowing in Mountlake Terrace
- Lawn fertilization in Mountlake Terrace
- Lawn dethatching in Lynnwood
- Lawn dethatching in Edmonds
- Lawn dethatching in Brier
Sources for the climate and the water
- USDA plant hardiness map for choosing plants that can take a Snohomish County winter.
- EPA WaterSense on watering less once a lawn or a new planting is established.
- EPA Soak Up the Rain on keeping roof and yard water from becoming someone else’s problem.
