Soil pH in Nobles, MN: Lime or Sulfur?

Typical topsoil pH in Nobles, MN

Typical topsoil in Nobles, MN is pH 6.62, already right for vegetable garden (6-7). Test before adding anything.

What Nobles needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, tomatoes, roses.
• Just outside, test first: strawberries (off by 0.1), pink hydrangeas (off by 0.1).
• Sulfur: potatoes 3.7 lb/100 sq ft over 2 applications; blueberries 5.4 lb/100 sq ft over 3 applications; azaleas and rhododendrons 4.8 lb/100 sq ft over 3 applications; blue hydrangeas 4.8 lb/100 sq ft over 3 applications.

What to do next

If your test lands near 6.62, 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 456,862 surveyed acres in Nobles, MN, 60% are near neutral (6.5-7.3), 31% are moderately acidic (5.5-6.5), 9% are alkaline (above 7.3). Mapped soils run from pH 5.7 to 7.9, a spread of 2.2 units across 324 soil components. 60% 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 30.2% clay and 5.48% organic matter, which this site treats as clay. At 5.48% organic matter the soil buffers like a heavier one, which pushes it into the clay bracket. Moving it one pH unit takes about 11.5 lb of lime or 3.4 lb of sulfur per 100 sq ft. 9% of mapped components carry free carbonate (lime already in the ground).

Nobles against the rest of Minnesota

pH 6.62 is right at the Minnesota median of 6.64. 40 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: Clearwater (6.57), Wright (6.58), Carver (6.59), Steele (6.6), Waseca (6.62), Blue Earth (6.64), Freeborn (6.64), Becker (6.65).

The range in Minnesota runs from Cook at 5.21 to Swift at 7.49; Nobles sits 62% of the way up.