How to Brew Worm Juice From Your Worm Farm

Many farmers are using their Worm Farms for the sole purpose of producing top-quality worm castings on-farm to brew into liquid extracts for various applications (e.g. seed dressings, fertigation, foliar sprays). Brewing takes the highly beneficial microbial populations in those castings and amplifies them, cultivating a thriving population of bacteria and fungi. These microbes boost nutrient uptake, supercharge seed germination, and toughen up plants against stress, giving you better yields with a reduction in input costs—all from your own farm. Here’s a basic way to brew that worm cast up right!

Brewing Basics

Typically farmers have an IBC/Shuttle readily available — these quantities are based off brewing 1000L of concentrate.

Gear

  • 100L Worm Mod castings
  • 1000L rainwater
  • IBC
  • Air pump connected to PVC pipe with 3mm holes drilled in (more holes, better aeration)
  • Mesh bag (for retaining castings)
  • 10L molasses (optional: fish hydrolysate or kelp)
  • Filter (aim for 200 microns, but check your sprayer)
Brewing Diagram

Steps

  1. Fill IBC with 1000L rainwater, hook up the air pump to PVC pipe with 3mm holes drilled in—keep oxygen above 4 ppm.
  2. Bag 100L castings, submerge, and stir.
  3. Add 10L molasses (plus 5–10L fish or kelp if needed), mix well.
  4. Aerate 24–36 hours—24 hours for bacterial dominance (great for annuals like wheat), 36 hours for fungal dominance (ideal for perennials like orchards). Target pH 6.5–7.4.
  5. Pull the bag, filter through 200-micron mesh (double-check your sprayer’s nozzle size), and apply fresh.
  6. Clean the IBC, pump, and pipes thoroughly after each brew—don’t let pathogens build up.
  7. You’ve just produced 1000L of a concentrate. Dilute with your typical water rates or apply directly. The benefit of brewing on-farm is that you can produce your concentrates for cents on the dollar—meaning you can bump up your application rates for maximum microbe application!

Storage Tip

Store leftover castings in a cool, dark spot in breathable bags.

Tweaking Your Brew

  • Nitrogen boost: Add fish hydrolysate.
  • Fungal focus: Mix in oatmeal, fish, kelps.
  • Need a custom recipe? Hit us up—we’ll tailor it.

Suppliers / Links

Here are some suggestions/examples with links! We haven't necessarily purchased from all of these links—they’re just examples of suitable options for you to explore. Feel free to message us if you have any questions about your particular equipment.

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