Determining Soil pH

Here within the luxurious Catican Compound, we have raised beds for flowers and vegetables and a wide array of potted plants, capped off, of course, by the radiant Momma Daisy. Wishing to be more scientific about our agriculture, we've recently decided to begin measuring soil chemistry and comparing the soil we provide our plants with the optimum soil characteristics recommended by experts. First up is soil pH. From answers.yahoo comes this set of instructions (modified a bit for grammar and spelling) for measuring pH:

1. Select soil, scoop it out and dry it under shade


2. After sieving, take 5 grams of soil and add 100 ml distilled water


3. Stir vigorously and filter through cotton wool or filter paper


4. Measure the pH of this liquid with test strips or a test meter

Perusing Amazon, we found that high quality pH test meters cost around $100. Unwilling to spend that much for this project, we discovered test strips which will measure pH in 0.5 increments. We figured we could eyeball interpolate or use Photoshop's pixel analysis capabilities on test strip digital photos to get a bit more accuracy on these strips and that they would do just fine.

An order has been placed and we expect to receive our test strips forthwith. Experimentation will follow.

Update: By comparison, the Oaktron pH2 handheld meter is accurate to 0.1, but costs much more and requires calibration. After writing the post above and heading to the checkout at Amazon with the test strips, I wondered if it was silly to not spend an extra $40 to get the handheld meter. The problem with the meter is that you also need calibration solutions - liquids of known pH that allow you to make sure the meter is accurate. That adds another $20 or so to the cost.

Maybe I should have gone this way, but the cost doesn't seem to warrant it.