Soil pH in Clear Creek, CO: Lime or Sulfur?

Typical topsoil pH in Clear Creek, CO

Typical topsoil in Clear Creek, CO is pH 6, already right for vegetable garden (6-7). Test before adding anything.

What Clear Creek needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, potatoes, strawberries, roses, azaleas and rhododendrons, pink hydrangeas.
• Just outside, test first: tomatoes (off by 0.2).
• Sulfur: blueberries 2.3 lb/100 sq ft over 2 applications; blue hydrangeas 1.8 lb/100 sq ft.

What to do next

If your test lands near 6, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, potatoes, strawberries, roses, azaleas and rhododendrons, pink hydrangeas.

How mixed the soil is

Of the 175,379 surveyed acres in Clear Creek, CO, 76% are moderately acidic (5.5-6.5), 17% are near neutral (6.5-7.3), 7% are strongly acidic (below 5.5). Mapped soils run from pH 5 to 7.2, a spread of 2.2 units across 259 soil components. 76% 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 13.2% clay and 1.48% 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. None of the mapped components carry free carbonate.

Clear Creek against the rest of Colorado

pH 6 is 1.17 below the Colorado median of 7.17. 2 of 63 Colorado counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.

Closest in pH within the state: San Juan (5.53), Hinsdale (5.93), Gilpin (6.24), Lake (6.37), Teller (6.41), Grand (6.42).

The range in Colorado runs from San Juan at 5.53 to Alamosa at 8.28; Clear Creek sits 17% of the way up.