Soil pH in Stearns, MN: Lime or Sulfur?

Typical topsoil pH in Stearns, MN

Typical topsoil in Stearns, MN is pH 6.69, already right for vegetable garden (6-7). Test before adding anything.

What Stearns needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, tomatoes, roses.
• Just outside, test first: strawberries (off by 0.2), pink hydrangeas (off by 0.2).
• Sulfur: potatoes 2.8 lb/100 sq ft over 2 applications; blueberries 3.9 lb/100 sq ft over 2 applications; azaleas and rhododendrons 3.2 lb/100 sq ft over 2 applications; blue hydrangeas 3.2 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 6.69, 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 764,426 surveyed acres in Stearns, MN, 56% are near neutral (6.5-7.3), 26% are moderately acidic (5.5-6.5), 16% are alkaline (above 7.3), 2% are strongly acidic (below 5.5). Mapped soils run from pH 5 to 8.2, a spread of 3.2 units across 433 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 17% clay and 3.72% 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. 19% of mapped components carry free carbonate (lime already in the ground).

Stearns against the rest of Minnesota

pH 6.69 is 0.05 above the Minnesota median of 6.64. 47 of 87 Minnesota counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Freeborn (6.64), Becker (6.65), Rock (6.67), Lake of the Woods (6.68), Scott (6.7), Cottonwood (6.72), Jackson (6.72), Otter Tail (6.73).

The range in Minnesota runs from Cook at 5.21 to Swift at 7.49; Stearns sits 65% of the way up.