Castings Tea Everything!


Testimonial Support

What is worm tea?

How Castings Tea works

Brewing instructions, ingredients, use

 As you may know earthworm castings tea and other compost teas have been around for some time.  Due to recent research and the rise of public interest in organic growing and planetary well-being they are now beginning to get the recognition they deserve.      

 Here are a few testimonials to support your interest to brew and use Castings Tea. 

 Don Wagoner, a former purveyor of all sorts of chemicals to grow and control things whom now thinks and lives differently: Link here

 More shining examples:

 “With the Microb-Brewer, the normally mundane task of keeping my soil ‘vibrant’ has become one of the few rewarding pleasures associated with soil management in organic farming.  A key advantage in using compost tea is the significantly reduced application time over conventional methods of applying bulk compost.  Even more important than the minimal labor requirements needed are the fact that this ‘aerobic teas’ is the most ‘alive’ solution you can apply to your crop.  Not only have we achieved healthier plants and higher yields, our fruit tastes as good as nature intended.”  Ed Leach, Umpqua Organic Farm, Roseburg, OR

 “We have found that compost teas controls weeds, disease and with added fish fertilizer provides all the nutrients needed by fescue turf grasses.  We have approximately 3 acres of turf.  This past summer we were able to skip water cycles for up to 4 consecutive days.  That’s with temperatures in July in excess of 110F with no signs of stress and full sun!!!  Tom Jaszewski, Las Vegas, NV  [Tom is perhaps the leading horticulturist in Las Vegas whom all leading casino horticulturists look to for advice.]

 “The compost tea used in my vineyard has worked particularly well.  The plants are really healthy and so is the soil …  With the tea, the mildew shows up, hovers, and goes away.  It never builds up enough steam to take over a tea sprayed area.  In the sulfur-sprayed areas, if there’s one to two percent mold one day, there will be 10 percent the next and 40 percent the day after that.”  Jeff Wilson, Owner, Territorial Vineyards & Wine Co., Veneta, OR 

“We were looking for a way to suppress turf grass disease without using fungicides.  We’ve seen positive results from using the tea, and we haven’t used fungicides for a long time.”  Troy Russell, Resort Superintendent, Brandon Dunes Golf Resort, Brandon, OR 

What is worm tea?

 We use the term ‘Castings Tea’ rather than ‘compost tea’ because we are a earthworm farm and are familiar with the differences of earthworm castings compared to other types of compost.  We therefore brew with our earthworm castings, although “compost tea” or CT is probably a more commonly used phrase than specifying the type of compost as we do, when we mention Castings Tea.  In both, microbiology is extracted from the microbial seed material with water so that the microbiology is in a liquid solution which can be sprayed – most often a far more convenient and feasible application method than bulk soil amending or dispersion.  The nature of Castings Tea vs. compost tea can be radically different with Castings Teas having more species diversity and worm created substances than compost teas and therefore offers more effective results.

 There are two types of Castings Teas: extracted and aerobically brewed.  In the extraction method, water is run through the earthworm castings to simply extract the microbes from the castings into the water. The resulting liquid solution is then applied in various ways.  Many bottled teas you see on the shelf use this method - the largest brand name of which is Terracycle.  In the brewing method, compost/castings are placed into a container of circulated and aerated water (via an air bubbler or similar system) typically with other nutrients.  The circulated water extracts the microbiology and the microbes are in an abundance of both oxygen and nutrient to feed upon.  In this method, colonies of microbes are brewed in exponential numbers, a colony of bacteria for instance can double in population every 20 minutes.  Aerobic brewing takes longer than basic extraction with common brewing times of 12 to 24 hours.  Brewing time is very dependant on water temperature with warmer water creating faster brews.  Aerobically brewed teas have much higher microbe population densities than extracted teas and for this reason are the tea of choice.  The sign of a good aerobically brewed tea is a good head of foam and scum on top signifying healthy microbe action!


How Casting Tea works

 Castings Tea is all about microbiology and is measured and evaluated under a microscope.  Compost, worm castings, EM, and other inoculants all work and are evaluated by this means also.  It is the wide diversity and numbers of microbiology that define a good tea.  Please refer to our April 2006 newsletter for a discussion of why this is important to healthy soil which, in turn, creates healthy and vibrant plant life.   April 2006 Newsletter

 Castings Teas suppress disease and pests on vegetation and will boost the crucial microbial activity known as the Soil Food Web (SFW) which is so crucial to organic soils.  Perhaps the most widely used and known use of teas is to suppress/eliminate black spot and powdery mildew on roses.  By spraying Castings Tea on the surface of leaves, you are doing two things.  First, you coat the leaf with millions if not billions of microbes all competing for a food source.  Some, for instance protozoa, eat bacteria which may be eating decaying plant material.  Others eat other microbes and their wastes.  In the end, there are not enough resources for the harmful molds and fungi to flourish.  In addition, you are also coating the leaf with a protective surface that protects the leaf cells from attack by foreign spores or airborne microbes.  Finally, by inoculating the soil with Castings Tea, microbes break down nutrients for uptake into plants thereby increasing plant health and the plant’s own disease resistance/suppression.

 Aerobically brewed Castings Tea is superior to basic compost teas because of the higher number and diversity of microbes, the additional substances that worms create and the reduction or lack of harmful microorganisms.  Although a traditional compost pile is a great environmental aid, and its final compost is a great value to your garden, it typically does not have the microbe species diversity and numbers of worm castings – especially when using Barefoot Soil Organic Earthworm Castings – to be an exceptional aid.  (Remember, microbial species diversity and numbers are necessary for a more thorough breakdown of the organic matter in any compost.)  A tea can only have the species diversity of the starting medium.  The only way to circumvent low numbers and diversity when brewing tea with a basic compost is to inoculate the tea itself during or at the end of the brew with catalysts, i.e. microbe packages!  Worms also create substances that act as growth hormones, cell length regulators, anti-aging compounds, and more goodies that just are not available in common compost.  Though different in quality either the brewing or extracting method will add these important aspects to teas, and this is the probable explanation of good results obtained by non-aerobic bottled tea that does not have high species diversity and numbers.  Finally, compost can also contain E.coli and other human pathogens if not composted properly.  In aerobic brewing and with adequate aeration maintenance, E.coli will not survive in the tea, because “there are many other organisms, which in aerobic conditions, grab food away from the E. coli, take up the space E. coli needs to grow, and consume E. coli.”  (2003, Dr. Elaine Ingram)   (An important note here:  “If you apply a source of questionable material anytime 120 days before you are going to eat those vegetables without washing them, there’s a possibility that E.coli could still be present, especially if your crop production system does not have adequate aerobic organisms to out-compete the coliforms.”  (2003, Dr. Elaine Ingram).


How to use Castings Tea

 Spray your plants liberally on the leaves, stems and surrounding soil.  Use them on turf.  Use them on clay soil to begin its transformation to humus.  Use them on your flowers indoors and out and on your other house plants. Use them on your compost pile to introduce the microbial activity and hasten the compost pile’s beneficial breaking down process.  Inoculate the ground surrounding your fruit trees.  Use them on manure piles that stink and marvel at how fast the stink and flies go away!  Use them on the small bucket of kitchen scraps you may have outside of your house.  Castings Tea everything!

 Foliar Spray/Wash:

 It’s best to spray all surfaces of your plants in the early morning or late afternoon when the sun's angle is low and has less strength.  When possible do your foliar spraying on a foggy, cloudy or clear days since rain may wash away some of the effectiveness. 

 Soil Inoculant - Drenching:

 Always apply teas out of direct sunlight.  Use them pure or dilute them (10:1 is a suggested maximum dilution rate).  Dilution ratios vary due to the manor or the characteristics of your application technique or equipment.  An ideal time is during light rains, mists, or fog.  Alternatively, irrigate a little before your treatment and after the application to insure the microbes will survive and travel more quickly and safely to their new job locations. Whenever possible use non-chlorinated water.

 If a tea stinks, do not use it on your vegetables as it is demonstrating anaerobic properties and may contain pathogens.  Dr. Ingram suggests you use it on an undesirable weed bed!

 A properly brewed Castings Tea is child, pet, and wildlife friendly.

 When we brew, there is a window of optimal application time when microbe populations and diversity are at their highest.  Best results occur when the Castings Tea is applied during its prime and is applied within 3 hours of being removed from the oxygen source.


Worm Castings Tea -  4 Gallon Brew Recipe



  4-8 cups Barefoot Soil Organic Earthworm Castings

¼ cup sulfur free molasses

1 Tbsp water soluble sea plant extract

2 Tbsp soluble fish powder or liquid fish

4+ gallons Chlorine free water


(Note:  If you have chlorinated water, fill your pail and let it sit overnight uncovered, and the chlorine will evaporate.  Alternatively, accelerate the process by putting the water in your brewer and turning the bubbler on.  You will know the chlorine is gone when you cannot smell the chlorine anymore – probably in as short a time as 20-30 minutes.  You can verify the absence of chlorine by purchasing a simple chlorine test kit from a local pool supplier.)

 Tea Brewer components:

 Min. 5 gallon plastic pail, bucket or barrel

Air pump with air stone or some other air dispersal device (remember: small bubbles are superior).

Sieve (a 5 gal. paint bucket filter works well)

Elastic band or a twist-tie to close the Sieve


 First, ensure that all components are clean and there are no buildups or areas of your brewer that will prevent the circulation of air and water.  (If the stone builds up residue just soak it overnight in pure white vinegar).

 In a 5 gallon pail, fill with 4 gallons or so of warm water with the molasses, seaweed extract, and liquid fish.  Turn on the pump with the hose and stone attached before placing the stone into the solution. Leave the pump running when removing the stone from the brew to keep water from entering the stone. 

 Place the air-stone or other bubbler at the bottom of the pail.  For best results, use the ‘open brew’ approach by placing the Barefoot Soil Organic Earthworm Castings directly into the water.  (You can always strain the castings later if you are going to use a sprayer for the Teas’ application.)  Alternatively, put the BFS Organic Earthworm Castings into the sieve and place it into the pail over the bubbler.

 Brew until a noticeable frothy slime (“bio-slime”) develops on the surface of the water and the smell of the ingredients is very weak or no longer present.  The absence of noticeable fish and molasses odor indicates that the microorganisms have consumed the ingredients!  Once the food is gone the populations will begin to decrease.  On warm summer days, you can begin a brew in the evening, and the tea will be ready for application the next morning.  We find brewing is complete in as little as 12 hours if the brew is kept warm.  Hence, brew times are heavily dependent on the water temperature.  With every 10 degree F drop in temperature, brew times increase by 12 hours.

 Be sure to keep the tea aerobic by leaving the bubbler on until you use the tea since cutting off the oxygen supply will down spike the population and diversity.

 While brewing, the population of beneficial microorganisms will be doubling in as little as every 20 minutes.  By the end of the brew, your solution can contain over one billion little critters per teaspoon of tea!

 Apply the tea when the populations of microorganisms are at their highest number and diversity.  Spray the tea onto foliage, stems, roots and surrounding soil, or simply pour it onto you plants and vegetation.  Remember, Castings Tea Everything!  Spray early morning or in the evening or in the shade, not in the sunshine.

 When you are finished, use the left over castings for your soil amendment needs.  Do not discard them!  These castings should have higher population densities than what you started with, because remember, you brewed an exceedingly large population, and they will adhere to the castings! 

Worm Tea Brewers & Nutrient Food

 Yelm Earthworm & Castings Farm offers a reasonably priced ‘work horse’ 5 gallon brew Kit as well as the necessary nutrient foods for the microbes.


Recommended Reading:  Teaming with Microbes, by Jeff Lowenfels

Perhaps the best site on teas:  Tim Wilson's: Microbe organics

Visit:  Dr Elaine Ingham's site: Soil Foodweb, Inc.


<<< Previous Page
  Copyright © 2003 Yelm Earthworm & Castings Farm