Soil pH in Calhoun, MI: Lime or Sulfur?

Typical topsoil pH in Calhoun, MI

Typical topsoil in Calhoun, MI is pH 6.2, already right for vegetable garden (6-7). Test before adding anything.

What Calhoun 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 6.2, 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 394,217 surveyed acres in Calhoun, MI, 69% are moderately acidic (5.5-6.5), 28% are near neutral (6.5-7.3), 3% are alkaline (above 7.3). Mapped soils run from pH 4.9 to 7.6, a spread of 2.7 units across 238 soil components. 69% 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 10.5% clay and 1.9% 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. 3% of mapped components carry free carbonate (lime already in the ground).

Calhoun against the rest of Michigan

pH 6.2 is 0.16 above the Michigan median of 6.04. 52 of 83 Michigan counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Leelanau (6.12), Van Buren (6.15), St. Joseph (6.16), Barry (6.19), Berrien (6.25), Kent (6.27), Presque Isle (6.27), Isabella (6.31).

The range in Michigan runs from Baraga at 4.72 to Huron at 7.03; Calhoun sits 64% of the way up.