Soil pH in Harmon, OK: Lime or Sulfur?

Typical topsoil pH in Harmon, OK

Typical topsoil in Harmon, OK is pH 7.4 and calcareous, so sulfur won't lower it for long. For vegetable garden, choose alkaline-tolerant varieties and add compost rather than fighting the soil.

What Harmon needs, by plant

• Beds or pots instead: lawn (cool-season grass), vegetable garden, tomatoes, potatoes, strawberries, roses, blueberries, azaleas and rhododendrons, blue hydrangeas, pink hydrangeas.

What to do next

If your test confirms pH near 7.4, consider raised beds for anything acid-loving; with 59% of soils here carrying free lime, sulfur will not hold.

How mixed the soil is

Of the 304,896 surveyed acres in Harmon, OK, 68% are alkaline (above 7.3), 20% are near neutral (6.5-7.3), 12% are moderately acidic (5.5-6.5). Mapped soils run from pH 5.8 to 8.2, a spread of 2.4 units across 164 soil components. 68% 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 23% clay and 1.21% 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. 59% of mapped components carry free carbonate (lime already in the ground), enough that sulfur gets neutralised before it does much.

Harmon against the rest of Oklahoma

pH 7.4 is 0.85 above the Oklahoma median of 6.55. 69 of 77 Oklahoma counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Custer (7.35), Greer (7.35), Washita (7.36), Tillman (7.38), Jackson (7.4), Dewey (7.41), Kiowa (7.41), Texas (7.48).

The range in Oklahoma runs from Adair at 5.12 to Beaver at 7.65; Harmon sits 90% of the way up.