|Here they are, fresh out of their shipping package and on their way to their new home!|
One of the first things I did upon moving in to my new apartment was to save one of my smaller moving boxes to start a little worm bin. I choose a box that a regular plastic grocery bag will easily line. I filled the bag/box about 1/3 full of organic potting soil, and then I collected a handful of clay and loam rich soil to add to the potting soil. (That was a gift from a gopher who makes his home along the local river.)
Worms need some fine mineral soil--they ingest it and it helps their digestion. The clay particles they ingest also supper-charge the worm castings. It seems that the clay-humus combination excreted by worms provides many plants with exactly what they need as far as nutrition is concerned, and also as far as the delivery method. Clay also contains cation exchange sites--which hold on to the nutrients until the microorganisms involved with the soil nutrient cycle present them with something in exchange.
There are microorganisms in the soil whose sole business is to trade nutrients they obtain from cation exchange sites with plant root hairs. What they get in the bargain are the carbohydrates that fuel their lives. The only source of carbohydrates, of course, are plants. They make them from sunlight and water using nutrients they exchange with microorganism in their root hairs.
In most natural environments here in North America, this all proceeds without the help of earthworms. There are very few earthworms indigenous to North America and they inhabit very small environmental niches. All most all the worms we encounter here were originally from Europe. And in fact, worms are not always a welcome part of natural environments. They can disrupt indigenous soil nutrient cycles and in some areas this is threatening native plant species and the organisms that depend on them. Just something to think about before you toss out worms leftover from fishing or before you introduce worms to your garden if you live adjacent to natural areas that do not already harbor earthworms.
Soil nutrient cycles can do what they need to do without earthworms, but where appropriate, worms supper-charge the process! They do their best work right in the soil of your garden, rather than in a worm bin or box. If you haven't already, check out my article on gardening with worms here:
The Compost Hole Method.