Earthworm Casting Application Rates

New Garden Soil Preparations:

  • Mix 1”- 4” of Earthworm Castings worked into the top 4” - 6” of soil in spring prior to planting or as soon as the ground becomes workable.

Seed Starting Mix: 

  • Add 1 part Earthworm Castings with 2 parts (fertilizer-free) peat or coconut coir based seed starting mix. 

 Annuals, Vegetables, or Perennials: 

  • Seeding: Line seeding trench, hole, or bed.
  • Transplanting: Add ½ - 1 cup Earthworm Castings to planting hole 
  • Established plants: Work 1 - 2 cups into top 2 - 3” of soil around plant.


  • Incorporate 2 - 4 cups into top 2 - 3” of soil in spring. 

 Potted Plants:

  • Apply 1 tablespoon for each 2 - 3” inches of pot diameter, gently work into soil, and water well.

 DIY Potting Soil:

  • 1 part worm castings
  • 1 part coco-coir
  • 1 part vermiculite or sand

When Applying Mulch:

  • Apply ¼" - ½" Earthworm Castings and cover with mulch to inoculate the mulch.  This will greatly increase the nutrient cycling ability of the applied mulch.

Compost Enhancer: 

  •  Broadcast Earthworm Castings throughout each layer of compost and lightly water-in.  This will ensure a diversity of biology is present to accelerate the composting process.

Home Brewed Actively Aerated Compost Tea

 (Please see our brewing and application guidlines under the Compost Tea tab at the top.)

Compost “Tea”:  Water weekly at normal rates for plants needs.

Mix 3 - 5 cups Earthworm Castings per 5 gallons of chlorine free water. (¼ - ½ cup for every 2 quarts of chlorine free water)

  • Aerate mixture by whisking/ stirring, or pouring from one bucket to another 2 or more times over the course of 24 - 48 hours.
  • For best results actively aerate mixture with a Garden Tea Brewer for 24 - 48 hours.  
  • Add 1 - 2 tbl. complex sugars (molasses, honey, agave, natural syrups, or fruit juices) per gallon of water per 24 hours of brew time. 

  We recommend brewing for at-least 12 to 48 hours.  The finished compost tea will be an amber to brown color much like a well brewed cup of tea.  Your compost tea should remain aerated until applied as the shelf life can be very short.  You can apply teas with a watering can as a soil drench or a with a pressurized sprayer.  Actively Aerated Compost Tea should be used immediately after removal from your aerobic tea brewing system.  The colonies of aerobic organisms can quickly consume the oxygen in the tea, and begin to die or go to dormant.  The un-aerated teas can be bottled and stored for several days in a cool dark place or in the refrigerator for up to one week.  Allow a 4" air gap in bottle.  Un-aerated, teas can lose as much as 30% - 50% of the biological diversity.  Un-aerated teas can still be useful unless the brew goes anaerobic.  You’ll know your tea has gone anaerobic if the tea has a strong foul odor.  Aerating and adding complex sugars will reactivate many of these dormant micro-organisms and return the tea to an aerobic state.

The home brewing of actively aerated compost teas provide a healthy alternative to toxic chemical fertilizers, herbicides, and pesticides.

Foliar Inoculant: (For more information please see our brewing and application guidelines for Compost Teas.)

Additional Compost Tea recipes are available here