Monroe sits on the Skykomish, with the fairgrounds on the edge of town. River-bottom ground stays wet, and a yard built as if the water table were low will heave, puddle, or grow moss until someone deals with the water. River-bottom lawns stay soft late into spring. Coring them early makes trenches. We wait, and we do not aerate ground that spent the winter underwater.
Snohomish County · ZIP 98272 · 2020 population 19,608
Do not core the part that floods
Low yards near the river have two surfaces: a bench that drains, and a corner that holds water until April. Only the bench is a lawn. The corner is a wet spot we should drain or plant as wet ground. Aerating it drives organic trash deeper and ruts the route we walked.
When the bench firms up, cores are useful because river soils can be fine and tight. We leave the plugs, overseed the thin spots, and stay off it for a week. A mower the next morning presses the holes shut.
The ground in Monroe
We see two kinds of lots. In town, smaller yards with the usual compacted soil and a lawn that has to look fine for most of the year. Closer to the river and the low ground, soils that remember high water. Gravel and drains belong there. A finished bark bed in a spot that floods is mulch in the neighbor’s fence line by spring.
The fair is part of the calendar. People want yards cleaned up and hedges cut back before the traffic and the guests, and they want storm debris gone after the first big fall wind. Trees on these lots — including the old fruit trees — need pruning that opens them up, not a topping that makes them dangerous. Native plantings along the wet edges do the work a lawn cannot.
How we do the work
We pull cores, we do not poke holes. A spike aerator squeezes the soil tighter around each puncture, which is the opposite of what a Western Washington lawn needs. Cores are about three inches, left on the grass to break apart in the rain. The visit is timed for soil that is moist enough to take the tine and dry enough that the machine does not leave ruts.
If the thatch is thicker than a finger, aerating through it only decorates the moss. Those lawns get dethatched first. Lime is a separate decision. A lot of local soil is sour, and we spread lime when the lawn shows it, not because a calendar said March.
What we look at first
- Thatch depth before we core
- Whether the ground ruts under foot
- Shade from trees that will keep the lawn thin no matter how often we aerate
- Downspouts dumping onto the same corner every winter
When we show up
The useful months are April into early June, and again in September. Midsummer cores on a dry lawn shatter and the holes collapse. January cores on saturated ground are ruts. We would rather wait a week than leave you with tracks.
What aeration will not fix
It will not move a downspout, kill a cedar’s shade, or drain a dish in the grade. If the lawn fails in the same circle every winter, we look at water and light before we sell you a third visit.
What we leave behind
Plugs on the grass for a few days, then they fall apart. You can mow when they crumble. Watering is only needed if we seeded and the week turned dry, which is rare here. Stay off the soft spots until the footprints disappear.
More from this crew
- Lawn aeration across Snohomish County
- Lawn dethatching in Monroe
- Lawn seeding in Monroe
- Lawn fertilization in Monroe
- Lawn mowing in Monroe
- Lawn aeration in Sultan
- Lawn aeration in Snohomish
- Lawn aeration in Gold Bar
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.
