Karl's Garden Blog

When we last saw our heros… wait, wrong blog. We left off last time on a cliffhanger — what will our first test results be? Well, the answer ends up being — not quite what we were looking for.

First, the pH test. pH stands for Potential Hydrogen, and is a measure of how acidic your soil is. Some plants like an acidic soil, some plants I took a small scoop of soil, got it down to the right size, added enough distilled water to get to the top line, and wrestled with the little capsule until I got most of the powder into the test container.

A few shakes later and — yep, neutral pH. Since the soil and compost were trucked in, this isn’t surprising in the least.

pH test of my garden soil

The next step is to take a larger sample and test the chemical contents of it. As a refresher course, we’re looking for Nitrogen, Potassium, and Phosphorus, which make up the three essential nutrients for plants.

The testing process is similar. After mixing the dirt and distilled water, I let it settle for more than 24 hours (About 30 hours total, to be precise) and then used the super-scientific pipette to transfer some of the clearer liquid from the container to the test containers. Then mix some of the mystery powder with the sample, and shake, and you should have your results.

And, if I may have a drumroll please, the results…

... the results make absolutely no sense.

… make absolutely no sense whatsoever.

Let’s remember what went into this dirt. First, we have two cubic yards of composted horse manure. It was mixed well with another two cubic yards or so of sandy riverbed loam — rich in sediments. Both are chock full of biologicals. Decomposed biologicals are the primary source of nitrogen. So how is this dirt deficient in nitrogen again?

I’ve got plenty of faults with the experimental protocol here. It’s SIMILAR to the process that would be used in an actual soil lab, but the controls are a bit… abstracted, and there’s a bunch of places for “user error” to affect the results. The sample size is decidedly too small for the pH test. And that’s just scratching the surface.

Stay tuned for part three, in which I call “bullshit” on the results and start testing other stuff.