Soil pH in Benton, MN: Lime or Sulfur?

Typical topsoil pH in Benton, MN

Typical topsoil in Benton, MN is pH 5.99, just outside the 6-7 range for vegetable garden. Test first; it may need nothing.

What Benton needs, by plant

• Already in range: potatoes, strawberries, azaleas and rhododendrons.
• Just outside, test first: lawn (cool-season grass) (off by 0), vegetable garden (off by 0), tomatoes (off by 0.2), roses (off by 0), pink hydrangeas (off by 0).
• Sulfur: blueberries 2.3 lb/100 sq ft over 2 applications; blue hydrangeas 1.6 lb/100 sq ft.

What to do next

If your test lands near 5.99, 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 259,290 surveyed acres in Benton, MN, 89% are moderately acidic (5.5-6.5), 10% are near neutral (6.5-7.3). Mapped soils run from pH 5.2 to 7.5, a spread of 2.3 units across 363 soil components. 89% 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 10.2% clay and 3.41% 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.

Benton against the rest of Minnesota

pH 5.99 is 0.65 below the Minnesota median of 6.64. 11 of 87 Minnesota counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.

Closest in pH within the state: Kanabec (5.91), Isanti (5.92), Cass (5.94), Mille Lacs (5.96), Morrison (5.99), Anoka (6.03), Itasca (6.04), Aitkin (6.06).

The range in Minnesota runs from Cook at 5.21 to Swift at 7.49; Benton sits 34% of the way up.