Worm Castings
The digested organic matter produced by earthworms, rich in beneficial microbes, balanced nutrients, and plant growth hormones.
What it is
Worm castings, also called vermicompost, are produced by earthworms as they digest organic material. They are one of the most biologically rich soil amendments available, containing beneficial bacteria, fungi, plant growth hormones, and a balanced array of plant-available nutrients. They are 100% natural and carry no risk of burning or over-application.
What it does
Castings improve soil structure and water retention, introduce billions of beneficial soil organisms per gram, and provide slow-release nutrients in plant-available forms. The plant growth hormones they contain stimulate root development and overall plant vigour. They also suppress certain soilborne pathogens through competitive microbial exclusion.
When to use
Incorporate into potting mix or seed-starting compost at any time. Apply as a top-dressing around established plants at the start of the season or as a mid-season boost. Can be brewed into worm-casting tea for a quicker, diluted foliar or drench application. Suitable year-round for container growing.
When not to use
There are no meaningful cautions associated with worm castings. Very high rates in container mixes can reduce drainage slightly, so balance with other amendments if making up potting media.
How to apply
- 1
For seed starting, blend worm castings at 10 - 20% of total potting mix volume with a quality peat or coir-based compost.
- 2
For transplanting, add a handful (1/4 - 1/2 cup) of worm castings to the planting hole and mix with the surrounding soil before setting in the plant.
- 3
As a top-dressing, spread a 1/2 - 1 inch layer of castings over the root zone from stem to drip line and water in gently.
- 4
For a liquid application, steep 2 cups of castings in 1 gallon of water for 24 hours, stirring occasionally, then apply the strained liquid as a root drench.
- 5
Repeat top-dressing applications every 4 - 6 weeks through the growing season for continued benefit.
Garden, by Willowbottom recommends only organic, wildlife-friendly solutions. No synthetic pesticides, no harmful chemicals - ever.