Soil pH in Sioux, ND: Lime or Sulfur?

Typical topsoil pH in Sioux, ND

Typical topsoil in Sioux, ND is pH 6.86, already right for vegetable garden (6-7). Test before adding anything.

What Sioux needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, roses.
• Just outside, test first: tomatoes (off by 0.1).
• Sulfur: potatoes 3.2 lb/100 sq ft over 2 applications; strawberries 2.1 lb/100 sq ft over 2 applications; blueberries 4.4 lb/100 sq ft over 3 applications; azaleas and rhododendrons 3.7 lb/100 sq ft over 2 applications; blue hydrangeas 3.7 lb/100 sq ft over 2 applications; pink hydrangeas 1.4 lb/100 sq ft.

What to do next

If your test lands near 6.86, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, roses.

How mixed the soil is

Of the 695,134 surveyed acres in Sioux, ND, 78% are near neutral (6.5-7.3), 16% are alkaline (above 7.3), 7% are moderately acidic (5.5-6.5). Mapped soils run from pH 6 to 8.8, a spread of 2.8 units across 752 soil components. 78% 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 19.6% clay and 2.69% 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. 16% of mapped components carry free carbonate (lime already in the ground).

Sioux against the rest of North Dakota

pH 6.86 is 0.34 below the North Dakota median of 7.2. 1 of 53 North Dakota counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Grant (6.85), Adams (6.87), Hettinger (6.88), Bowman (6.94), Stark (6.94).

The range in North Dakota runs from Grant at 6.85 to Pembina at 7.5; Sioux sits 2% of the way up.