Worm Castings: The Gentle Fertiliser Plants Love
What worm castings are, why they work, and how to use them on seedlings, vegetables and houseplants.
What are worm castings?
Worm castings are the rich material left after earthworms digest organic matter. They contain nutrients in a form plants can use and are full of beneficial microbes, yet they are gentle enough not to burn roots.
How to use them
Mix about one part castings to four parts potting mix for seedlings and containers. Sprinkle a handful around vegetables as a top dressing, or steep a cup in a bucket of water overnight for a mild liquid feed.
Quick tips
- Great for seedlings
- Safe for houseplants
- Store them slightly moist
Make your own
A worm bin with red wiggler worms turns kitchen scraps into castings in a few months. It fits under a sink or on a balcony and does not smell when kept balanced.
