Soil pH in Laramie, WY: Lime or Sulfur?

Typical topsoil pH in Laramie, WY

Typical topsoil in Laramie, WY is pH 7.42, too alkaline for vegetable garden. Expect roughly 2.1 lb of sulfur per 100 sq ft, but only after a soil test confirms it.

What Laramie needs, by plant

• Sulfur: lawn (cool-season grass) 2.1 lb/100 sq ft over 2 applications; vegetable garden 2.1 lb/100 sq ft over 2 applications; tomatoes 2.1 lb/100 sq ft over 2 applications; potatoes 4.4 lb/100 sq ft over 3 applications; strawberries 3.2 lb/100 sq ft over 2 applications; roses 2.1 lb/100 sq ft over 2 applications; blueberries 5.5 lb/100 sq ft over 3 applications; azaleas and rhododendrons 5.1 lb/100 sq ft over 3 applications; blue hydrangeas 5.1 lb/100 sq ft over 3 applications; pink hydrangeas 2.8 lb/100 sq ft over 2 applications.

What to do next

If your test confirms pH near 7.42, work in about 21 lb of elemental sulfur per 1,000 sq ft of vegetable bed in 2 doses.

How mixed the soil is

Of the 1,529,943 surveyed acres in Laramie, WY, 63% are near neutral (6.5-7.3), 37% are alkaline (above 7.3). Mapped soils run from pH 6.7 to 8.8, a spread of 2.1 units across 323 soil components. 63% 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 17% clay and 2.06% 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. 25% of mapped components carry free carbonate (lime already in the ground).

Laramie against the rest of Wyoming

pH 7.42 is 0.08 below the Wyoming median of 7.5. 8 of 23 Wyoming counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Sheridan (7.25), Hot Springs (7.34), Johnson (7.35), Campbell (7.37), Niobrara (7.42), Converse (7.5), Weston (7.5), Goshen (7.55).

The range in Wyoming runs from Teton at 6.19 to Carbon at 8.31; Laramie sits 58% of the way up.