I admit I was concerned about this one. Normally tests aren’t a problem for little Miss Clever-Clogs here, but this one required years of study, some experimentation in the lab, and more than a pinch of intuition. And it was the kind of test that if you failed it, you’d have to do some serious remediation before you could take it again and expect to achieve better results. So I’m happy to report that all my cramming evidently has borne fruit: I aced my soil test.
You are seriously underwhelmed, aren’t you?
Yeah, OK, I didn’t get into Harvard (congratulations, Malia Obama!), nor did I qualify for a stint on the International Space Station or have one of my books nominated for an award. But, by jeezum, I grow a pretty darned good garden soil, and I have the test results from the Soil Testing Service at the University of Maine to wave under people’s noses to prove it.
Which I probably will not do. Modesty is becoming in such situations, I understand.
Oh, for years I talked a good game, seeming knowledgeable about pH levels, greensand, Epsom salts, seaweed, and the efficacy of various types of manure from cow flops to bat guano. People admired my tomatoes, zucchini, and rainbow chard, my raised beds, and the tower-of-power that is my compost pile, and I basked in the glow of their praise. But there was that little voice sometimes in the wee hours or the weeding hours, the insidious Worm in my Garden of Eden that wanted to know why, if I was doing everything right, the ends of the young zucchinis rotted before they could grow, or why the tomatoes just didn’t look as lush as they should. Had I dug in enough seaweed, or too much? Had the wood shavings mixed in with the manure made the soil less able to hold water long enough to do my plants any good? Had I done something horrid to the hard-working soil by dumping the ashes from the pellet stove on it in the winter? Was I a fraud for thinking I was a pretty good gardener, while all the time, under the soil, Something had gone seriously wrong?
It might easily have done so, after all. I have grown vegetables in the same seven raised beds for a quarter century or more. That’s a long time to draw nutrients out of the soil if you aren’t putting back the right stuff to replenish it.
The past three seasons, in particular, gave me the uneasy sense that something wasn’t quite right. It’s true that the weather’s been wonky, all over the place, really, and weather is always what I blame for poor crops or credit for good ones. What if it wasn’t the weather, though? Determined to get some answers, I picked up a soil sampling kit offered by the local Cooperative Extension.
I had never had a professional soil test done, though I have occasionally played with those home versions where the color intensity of the soil-water mix in the little vial is supposed to indicate how much nitrogen, phosphorus, and potassium are present in your soil, and what the pH level is. The last home test I did showed no reaction in any of the vials, indicating either the chemicals in the kit were dead, or my soil was. You can understand my concern. But getting a real soil test done seemed something only a big, commercial farm would need. If you’re cultivating acres and your livelihood depends upon that land producing at peak efficiency, sensible management dictates you’d want all the facts on exactly what’s going on in your soil. When I looked over the form I was to send with my sample, however, I was pleased to find that not only could I enter the size of my arable land in acres or in square feet, I could also indicate this sample was from a home garden, managed organically. So I proudly entered 270 square feet for the size of 2Dits Farm (I bet I made some graduate student grin when she or he conducted this test!), collected the 15 different soil samples from different places in the raised beds, mixed this dirt together, picked out the earthworms, and mailed off a pint to the testing service.
A little over two weeks later I got the results. I’m still ‘unpacking’ the implications of some of the numbers, but the highlights show that things are humming right along Down Where the Microbes Are. The optimum pH level (basically how acidic or alkaline the soil is in non-gardener speak) for vegetables is between 6.0 and 7.0, with 6.5 to 6.8 being preferred. Mine is 6.9, which is fine but does explain why my acid-lovers, chiefly tomatoes and potatoes, who’d rather hang out down around 6.0 to 6.5, aren’t quite as happy as they could be. The barest dusting of sulfur worked into the soil before planting would lower the pH for them without having a serious impact on whatever I will plant in those raised beds on next year’s rotation. I’d already planted this year’s potatoes before I got the report, but I will amend the soil for the tomatoes before I plant them.
Results for major nutrients like phosphorus, potassium, calcium, and magnesium are in the optimum or above optimum range. I’ve been a little too heavy-handed with the bone meal, apparently, so the phosphorus level is 344 lb./acre, well above the optimum range of 20-40 lb./acre. No more bone meal, not for awhile. On the other hand, the eggshells and broken mussel shells I add are doing a good job of providing calcium, which is nice to know and helps my tomatoes never to have blossom end rot.
In fact, the only recommendations the folks at the testing service have for me are to add seven pounds or so of bloodmeal to supply nitrogen, and about two pounds of alfalfa meal for potassium and nitrogen. (Nitrogen is water-soluble, so it needs to be replenished each growing season.)
The part of the report of which I’m proudest, though, is the Soil Microbial Biomass Test, which measures how much organic matter is readily available to feed the beneficial microbes in your soil over the course of the growing season. According to the test, my garden scored “Ideal biological activity and soil organic matter content.” In practical terms, this means I need only a seasonal cover crop (for instance, Dutch white clover sown between the tomatoes as a low-growing, living mulch) or a thin layer of compost on the raised beds this year because they’re so fertile they need nothing else.
In non-practical terms, the test is wonderful confirmation that my sometimes by-guess-and-by-golly attempts to create as healthy a garden as I’m able have actually paid off. The backaches from hauling seaweed and manure, and from turning under cover crops of clover, oats, and buckwheat to enrich the soil have all been worth it.
I guess I can call myself a gardener now.