Soil pH in Dewey, OK: Lime or Sulfur?

Typical topsoil pH in Dewey, OK

Typical topsoil in Dewey, OK is pH 7.41 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 Dewey 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 7.41, consider raised beds for anything acid-loving; with 47% of soils here carrying free lime, sulfur will not hold.

How mixed the soil is

Of the 593,680 surveyed acres in Dewey, OK, 59% are alkaline (above 7.3), 37% are near neutral (6.5-7.3), 3% are moderately acidic (5.5-6.5). Mapped soils run from pH 5.3 to 8.2, a spread of 2.9 units across 111 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 14.6% clay and 1.14% 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. 47% of mapped components carry free carbonate (lime already in the ground), enough that sulfur gets neutralised before it does much.

Dewey against the rest of Oklahoma

pH 7.41 is 0.86 above the Oklahoma median of 6.55. 71 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: Washita (7.36), Tillman (7.38), Harmon (7.4), Jackson (7.4), Kiowa (7.41), Texas (7.48), Cimarron (7.49), Harper (7.49).

The range in Oklahoma runs from Adair at 5.12 to Beaver at 7.65; Dewey sits 91% of the way up.