Soil pH in Clinton, IL: Lime or Sulfur?

Typical topsoil pH in Clinton, IL

Typical topsoil in Clinton, IL is pH 6.4, already right for vegetable garden (6-7). Test before adding anything.

What Clinton needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, tomatoes, strawberries, roses, pink hydrangeas.
• Sulfur: potatoes 2.1 lb/100 sq ft over 2 applications; blueberries 3.2 lb/100 sq ft over 2 applications; azaleas and rhododendrons 2.8 lb/100 sq ft over 2 applications; blue hydrangeas 2.8 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 6.4, 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 298,373 surveyed acres in Clinton, IL, 50% are near neutral (6.5-7.3), 50% are moderately acidic (5.5-6.5). Mapped soils run from pH 5.8 to 7.3, a spread of 1.5 units across 120 soil components. No single class covers 60% of the county, so two gardens a few miles apart here can need opposite treatments. Test your own bed.

Clay, organic matter and rates

Topsoil here averages 19.7% clay and 2.26% 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. 1% of mapped components carry free carbonate (lime already in the ground).

Clinton against the rest of Illinois

pH 6.4 is right at the Illinois median of 6.4. 49 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: St. Clair (6.38), Brown (6.39), Pike (6.39), Stark (6.39), Hancock (6.4), Mason (6.4), Piatt (6.4), Carroll (6.41).

The range in Illinois runs from Pope at 5.5 to Grundy at 6.75; Clinton sits 72% of the way up.