Soil pH in Shawnee, KS: Lime or Sulfur?

Typical topsoil pH in Shawnee, KS

Typical topsoil in Shawnee, KS is pH 6.23, already right for vegetable garden (6-7). Test before adding anything.

What Shawnee needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, tomatoes, strawberries, roses, pink hydrangeas.
• Just outside, test first: potatoes (off by 0.2), azaleas and rhododendrons (off by 0.2).
• Sulfur: blueberries 4.1 lb/100 sq ft over 3 applications; blue hydrangeas 3.4 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 6.23, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, potatoes, strawberries, roses, azaleas and rhododendrons, pink hydrangeas.

How mixed the soil is

Of the 336,878 surveyed acres in Shawnee, KS, 71% are moderately acidic (5.5-6.5), 23% are near neutral (6.5-7.3), 6% are alkaline (above 7.3). Mapped soils run from pH 5.6 to 7.9, a spread of 2.3 units across 451 soil components. 71% 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 30.1% clay and 3% organic matter, which this site treats as clay. Moving it one pH unit takes about 11.5 lb of lime or 3.4 lb of sulfur per 100 sq ft. 6% of mapped components carry free carbonate (lime already in the ground).

Shawnee against the rest of Kansas

pH 6.23 is 0.34 below the Kansas median of 6.57. 19 of 105 Kansas counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Harvey (6.22), Stafford (6.22), Allen (6.23), Johnson (6.23), Labette (6.24), Neosho (6.25), Ottawa (6.25), Wilson (6.25).

The range in Kansas runs from Cherokee at 5.95 to Wallace at 7.51; Shawnee sits 18% of the way up.