Year 2 in the garden. It’s past time I tested the nutrient levels in my soil. I have a variety of beds so I bought a test kit. Although the kit advertizes ’40 tests’, the fine print reads (10 each for N, P, K, pH). So really, it’s only 10 tests. Bummer.
I follow the instructions, taking a mixed sample of soil from a few inches down. I mix in water at 1:5. I wait for the fine particulates to settle.
First thing I notice is that I have some very different soil across my beds. The best is my main garden, which is nicely dark, moist, and well-structured. Sub-standard are the beds out by the street which are pretty dry, light, and friable, and the bottle bed, which has a lot of clay.
The tests showed normal pH, high P, high K, and … zero N. Really? No nitrogen? In all the beds? I run through the possibility. Before last year, the main garden was grass – a N-sucker. Plus we live in the PNW where it rains a lot, which would leach nutrients. Yes, I had skimped on the amount of compost I dug into the soil the first year, and yes, some plants were struggling by the end of the season. So I suppose it’s possible the N is completely depleted.
Manure? Fish emulsion? What to do – and how much? I called a local hotline to ask for advice.
Turns out you cannot reliably measure nitrogen in the soil in spring. Oh that’s rich (or depleted…whatever). The nice lady at Seattle Tilth told me that the local county extension doesn’t even offer soil nitrogen testing in spring. Although not likely at zero, my soil nitrogen probably is depleted, for the reasons stated above. Seattle Tilth recommended 3-4″ of compost dug in now and some mid-season side-dressing. Easy enough. But it would have been nice if the soil test kit had told me to wait until fall.