All dirt is not created equal. One of the challenges of gardening is to try and build ideal soil, soil that will provide a healthy medium for growing food that has the highest possible nutritional value. Most gardeners get the idea that we have to feed our garden to enrich it with nutrients that the plants will incorporate into our food. We add manures or compost (or both) plus fertilizer and trust that we have the right mix. Hopefully, we know where our additives come from because a lot of what you buy at the home and garden center isn’t just manure—it’s crap. You’ll think you are improving your soil but you could be making it worse.
Part of what we are trying to accomplish is to build the soil/life web but this is only part of the goal. In the Pacific NW the rains leach nutrients from soil. Beds can be protected over the winter by heavy mulching or even covering them with black plastic. At some point, though, in our quest to improve the nutritional value of our produce we need to take a hard look at the mineral balance of our soil.
The details of soil science get a bit complicated for me but the gist of it is there are lots of chemical actions taking place in the garden and it’s important to have the right balance of minerals to get the best results from your efforts. Michael Astera is the go to guy these days for soil science and his self-published book The Ideal Soil now available from Amazon lays it all out in detail.
The nice thing is that you don’t have to understand the details. You just need to buy into the concept that soil system, not unlike the human system, has to have the proper balance of nutrients to function properly. It’s pretty simple and not cost prohibitive to have your soil tested. Even without a professional evaluation you will begin to see where your soil has deficiencies. You can get a soil test from outfits like Logan Labs . Black Lake Organics in Olympia is a source for all those hard to find minerals.
You can get someone, even Michael Astera, to evaluate your test a give you a prescription. The two parts, test and evaluation cost about $20 and $60 respectively which might not seem worth it for a small garden. On the other hand, it’s hard to put a price on top nutrition and a garden whose immune system is strong enough to fight off bugs and disease, which is only one of the benefits of balanced soil.