Gardeners get excited about worm poop, or “castings,” they might say, when they want to sound a little more sophisticated about it. Why get so excited about it? Here are the many reasons:
Earthworm castings are full of organic matter and beneficial microorganisms that serve the soil beyond what most fertilizers can accomplish. They contain low levels of essential plant nutrients, but won’t burn plant roots, as too high an amount or concentrate of most fertilizers can. With more humus than traditional compost or normal garden soil, castings improve soil structure, improve soil aeration, and better retain water and valuable nutrients – which would otherwise rinse right through poor-quality soil. All of this helps those nutrients and microorganisms stay in the soil, keeping it fertile, feeding the plants, and… attracting more earth worms and their poop. This rich soil environment creates a self-sustaining cycle of fertility over the long term. That is why many gardeners will tell you: be less interested in feeding the plant, and more interested in feeding the soil.
So as a gardener, that’s a lot to be excited about!