Question: Can I make my soil better by adding worms to the garden?
Answer: Sorry, no. But read on.
We all love worms, and know on some level that they belong in the category of “good bugs”, but the relationship between the worm and the garden is sometimes confusing. Worms are beneficial to the garden because they eat decomposing organic matter. They are an accelerant to healthy soil, but only if they have enough food. So dumping worms on starved ground is useless at best and probably an act of second degree wormicide.
The worms that gardeners particularly covet are colloquially called Red Wigglers. These petite, glossy burgundy little guys are very active, and particularly efficient at eating leaves, duff, compost, and other organic material. Their poop, called castings, is made up of this organic material already broken down and ready to work for you, improving drainage and aeration in the soil, as well as increasing fertility.
Red wigglers aren’t known to be all that cold tolerant, but the ones that found my compost pile years ago make it through the Philadelphia winter. They seem to go dormant in the cold but pick up where they left off once it’s spring and begin processing anything edible in their path.
And spring is a good time to think about starting to improve your soil, which will take time. The cheapest, easiest way is to start composting, but if that’s not possible, organic material can be purchased as well. At least once a year, use a combination of three parts humus (which is made up of composted organic stuff) to one part composted manure, spread two or three inches deep. Mushroom soil can also be used in place of humus. What’s cool is that by adding this material somewhat regularly, over time the worms will find this improved habitat on their own, and a symbiotic relationship will form. The worms will have ample amounts to eat, and will improve the soil structure by their tunneling and their castings.