Soil pH in McDonough, IL: Lime or Sulfur?

Typical topsoil pH in McDonough, IL

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

What McDonough 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 2.8 lb/100 sq ft over 2 applications; blue hydrangeas 2.3 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 366,098 surveyed acres in McDonough, IL, 65% are moderately acidic (5.5-6.5), 35% are near neutral (6.5-7.3). Mapped soils run from pH 5.8 to 7.3, a spread of 1.5 units across 168 soil components. 65% 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 23.6% clay and 3.24% organic matter, which this site treats as loam. Moving it one pH unit takes about 7 lb of lime or 2.3 lb of sulfur per 100 sq ft. None of the mapped components carry free carbonate.

McDonough against the rest of Illinois

pH 6.23 is 0.17 below the Illinois median of 6.4. 16 of 102 Illinois counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Effingham (6.17), De Witt (6.21), Richland (6.21), Jackson (6.22), Calhoun (6.25), Jasper (6.25), Alexander (6.27), Clay (6.27).

The range in Illinois runs from Pope at 5.5 to Grundy at 6.75; McDonough sits 58% of the way up.