Soil pH in Pend Oreille, WA: Lime or Sulfur?

Typical topsoil pH in Pend Oreille, WA

Typical topsoil in Pend Oreille, WA is pH 6.49, already right for vegetable garden (6-7). Test before adding anything.

What Pend Oreille needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, tomatoes, strawberries, roses, pink hydrangeas.
• Sulfur: potatoes 1.2 lb/100 sq ft; blueberries 1.8 lb/100 sq ft; azaleas and rhododendrons 1.4 lb/100 sq ft; blue hydrangeas 1.4 lb/100 sq ft.

What to do next

If your test lands near 6.49, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, strawberries, roses, pink hydrangeas.

How mixed the soil is

Of the 760,103 surveyed acres in Pend Oreille, WA, 74% are near neutral (6.5-7.3), 25% are moderately acidic (5.5-6.5), 1% are strongly acidic (below 5.5). Mapped soils run from pH 5 to 8.2, a spread of 3.2 units across 1,298 soil components. 74% of the land falls in one class, so the county figure is a fair first guess for most yards here.

Clay, organic matter and rates

Topsoil here averages 8.2% clay and 3.27% organic matter, which this site treats as sandy. Moving it one pH unit takes about 3 lb of lime or 1.2 lb of sulfur per 100 sq ft. 0% of mapped components carry free carbonate (lime already in the ground).

Pend Oreille against the rest of Washington

pH 6.49 is 0.08 above the Washington median of 6.41. 22 of 39 Washington counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Skamania (5.86), Spokane (6.41), Okanogan (6.45), Kittitas (6.47), Chelan (6.5), Klickitat (6.53), Ferry (6.61), Stevens (6.73).

The range in Washington runs from Grays Harbor at 4.93 to Adams at 7.45; Pend Oreille sits 62% of the way up.