Soil pH in Knox, NE: Lime or Sulfur?

Typical topsoil pH in Knox, NE

Typical topsoil in Knox, NE is pH 6.97, already right for vegetable garden (6-7). Test before adding anything.

What Knox needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, roses.
• Just outside, test first: tomatoes (off by 0.2).
• Beds or pots instead: potatoes, strawberries, blueberries, azaleas and rhododendrons, blue hydrangeas, pink hydrangeas.

What to do next

If your test lands near 6.97, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, roses.

How mixed the soil is

Of the 706,865 surveyed acres in Knox, NE, 44% are near neutral (6.5-7.3), 37% are alkaline (above 7.3), 18% are moderately acidic (5.5-6.5), 1% are strongly acidic (below 5.5). Mapped soils run from pH 5.4 to 8.2, a spread of 2.8 units across 439 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 24.2% clay and 2.35% 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. 37% of mapped components carry free carbonate (lime already in the ground), enough that sulfur gets neutralised before it does much.

Knox against the rest of Nebraska

pH 6.97 is 0.22 above the Nebraska median of 6.75. 73 of 93 Nebraska counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Keith (6.93), Stanton (6.93), Thurston (6.93), Frontier (6.97), Merrick (6.97), Dixon (7), Red Willow (7.02), Cedar (7.03).

The range in Nebraska runs from Fillmore at 5.88 to Scotts Bluff at 7.58; Knox sits 64% of the way up.