pH Analysis Procedures

Adding Dye to Soil Sample

Testing soil pH will help ensure that you're getting the healthiest and biggest yield of crops from your garden. pH is a measurement of how acidic an entity is. Conducting a soil pH test is the best way to find out how acidic your soil is. Different types of plants have different requirements for their optimal pH level. By testing soil pH in each garden bed at Sage, they will have the opportunity to provide the garden it's best opportunity for having successful growing conditions. Placing plants in garden soil that does not match their pH needs can weaken the plants. Most plants will grow well in soils that test within a pH level in the range of 6.5 to 7.0.

pH testing was performed in the lab for all six samples that were taken from Sage Garden. The test was done by saturating a small sample of each soil with a selected dye, swirling lightly to mix, and then comparing the color to the colors on the pH scale.

Dyes for pH Testing

Color Matching - not so easy!

The soil dyes used were:
Bromcresol Green for pH 3.8-5.4
Chlorophenol Red for pH 5.2-6.8
Bromythol Blue for pH 6.0-7.4

The results were:
Soil Reference Western Oregon sample - 6.4
Sample 1 - 5.8
Sample 2 - 5.6
Sample 3 - 5.4
Sample 4 - 5.6
Sample 5 - 5.4
Sample 6 - 5.6

The reference soil, “Soil Reference Western Oregon “ or SRW, is known to have a pH of 6.2. Our reading was within the margin of error, so the other readings are probably reasonably accurate too. The Soil Survey data for Willamette Silt Loam indicates a range of pH 5.6-5.9, so the SAGE soil is generally within that range.