Soil pH in Pennington, SD: Lime or Sulfur?

Typical topsoil pH in Pennington, SD

Typical topsoil in Pennington, SD is pH 6.94, already right for vegetable garden (6-7). Test before adding anything.

What Pennington needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, roses.
• Just outside, test first: tomatoes (off by 0.1).
• Sulfur: potatoes 4.8 lb/100 sq ft over 3 applications; strawberries 3.1 lb/100 sq ft over 2 applications; blueberries 6.5 lb/100 sq ft over 4 applications; azaleas and rhododendrons 5.8 lb/100 sq ft over 3 applications; blue hydrangeas 5.8 lb/100 sq ft over 3 applications; pink hydrangeas 2.4 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 6.94, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, roses.

How mixed the soil is

Of the 1,776,658 surveyed acres in Pennington, SD, 51% are near neutral (6.5-7.3), 29% are alkaline (above 7.3), 19% are moderately acidic (5.5-6.5), 1% are strongly acidic (below 5.5). Mapped soils run from pH 4.5 to 8.8, a spread of 4.3 units across 1,140 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 29.3% clay and 2.81% organic matter, which this site treats as clay. Moving it one pH unit takes about 11.5 lb of lime or 3.4 lb of sulfur per 100 sq ft. 26% of mapped components carry free carbonate (lime already in the ground).

Pennington against the rest of South Dakota

pH 6.94 is 0.05 below the South Dakota median of 6.99. 27 of 66 South 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: Buffalo (6.9), Davison (6.91), Kingsbury (6.91), Jerauld (6.93), Todd (6.94), Hamlin (6.95), Bon Homme (6.97), Corson (6.97).

The range in South Dakota runs from Lawrence at 6.49 to Jones at 7.47; Pennington sits 46% of the way up.