Will a Worm Population Double in 3 Months?

Many seasoned worm growers will claim that their worm population will double in 3 months - and they believe it. That seems an extraordinary claim to make, so let's actually work the numbers and see the result. 

So, here's the numbers and  assumptions.

We start with an easy number - 100 Eisenia fetida - the most common compost worm

Then we assume:-

  • Conditions are ideal – 25oC/77oF temps – good moisture,  enough food etc    
  • 4 cocoons produced per adult worm per week
  • 4 juvenile worms hatching from each cocoon
  • 21 days  until cocoons hatch
  • 42 days to maturity
  • 12 week period.
  • we count the cocoons at the end of each week.
  • No worms die on us.


 100 Adults


100 Adults
400 Cocoons (A)


100 Adults
400 Cocoons (A) – 7 days old
400 Cocoons (B)


100 Adults
400 Cocoons (A) – 14 days old
400 Cocoons (B) – 7 days old
400 Cocoons (C)


100 Adults
1600 Juveniles (A)
400 Cocoons (B) – 14 days old
400 Cocoons (C) – 7 days old
400 Cocoons (D)


100 Adults
1600 Juveniles (A) – 7 days old
1600 Juveniles (B)
400 Cocoons (C) – 14 days old
400 Cocoons (D) – 7 days old
400 Cocoons (E)


100 Adults
1600 Juveniles (A) – 14 days old
1600 Juveniles (B) – 7 days old
1600 Juveniles (C)
400 Cocoons (D) – 14 days old
400 Cocoons (E) – 7 days old
400 Cocoons (F)


100 Adults
1600 Juveniles (A) – 21 days old
1600 Juveniles (B) – 14 days old
1600 Juveniles (C) – 7 days old
1600 Juveniles (D)
400 Cocoons (E) – 14 days old
400 Cocoons (F) – 7 days old
400 Cocoons (G)


100 Adults
1600 Juveniles (A) – 28 days old
1600 Juveniles (B) – 21 days old
1600 Juveniles (C) – 14 days old
1600 Juveniles (D) – 7 days old
1600 Juveniles (E)
400 Cocoons (F) – 14 days old
400 Cocoons (G) – 7 days old
400 Cocoons (H)

WEEK 10 

100 Adults
1600 Juveniles (A) – 35 days old
1600 Juveniles (B) – 28 days old
1600 Juveniles (C) – 21 days old
1600 Juveniles (D) – 14 days old
1600 Juveniles (E) – 7 days old
1600 Juveniles (F)
400 Cocoons (G) – 14 days old
400 Cocoons (H) – 7 days old
400 Cocoons (I)

WEEK 11 

1700 Adults (A)
1600 Juveniles (B) – 35 days old
1600 Juveniles (C) – 28 days old
1600 Juveniles (D) – 21 days old
1600 Juveniles (E) – 14 days old
1600 Juveniles (F) – 7 days old
1600 Juveniles (G)
400 Cocoons (H) – 14 days old
400 Cocoons (I) – 7 days old
400 Cocoons (J)

WEEK 12 

3300 Adults (A) – 1 week old.   These will produce 4 cocoons each =13,200*
1600 Adults (B)
1600 Juveniles (C) – 35 days old
1600 Juveniles (D) – 28 days old
1600 Juveniles (E) – 21 days old
1600 Juveniles (F) – 14 days old
1600 Juveniles (G) – 7 days old
1600 Juveniles (H)
400 Cocoons (I) – 14 days old
400 Cocoons (J) – 7 days old
400 Cocoons (K)
13200 Cocoons (A-1)


4,900 Adults  which will produce 19,600 cocoons                                                                                                                                                                 1,600 Adults


1600 Juveniles (D) – 35 days old
1600 Juveniles (E) – 28 days old
1600 Juveniles (F) – 21 days old
1600 Juveniles (G) – 14 days old
1600 Juveniles (H) – 7 days old
1600 Juveniles (I)
400 Cocoons (J) – 14 days old
400 Cocoons (K) – 7 days old
400 Cocoons (L)
19,600 cocoons


6,500 Adults
9,600 Juveniles
20,800 Cocoons   

and we started with 100 !       Extend the math a little further just to see what happens. 

Our conditions were ideal and none died.    But, there's nothing to say at various times during a year, your worm bed conditions won't also be ideal and it's very unusual to find worms dying.

But bear this in mind.    A doubling of population, does not mean a doubling in mass.    4000 mature E.fetida may weigh one kilogram, but 8000, being 4000 mature and 4000 hatchlings won’t weigh 2 kilos.

Organic Growing with Worms

(A short sample) 

By David Murphy

About the Author

David Murphy is an Australian.   He is a retired tanner who developed a deep interest in recycling organic wastes to repair degraded agricultural soils by natural agents and practices, striving to provide the means of developing a naturally renewable soil fertility.   For eight years he was Vice President of The Australian Worm Growers Association, a founding member of Compost Victoria and Chair of the Compost Quality Portfolio.  He works as a Consultant to Industry and Government within Australia and Internationally on stabilising organic wastes for producing beneficial soil additives by large scale Vermiculture and Aerobic Composting.   He is a recognised authority on organic waste stabilisation.  



To Mother Nature

Who always knows best

© David J. Murphy 2013

This book is copyright.   Apart from any fair dealing for the purposes of private study, research, criticism or review, as permitted under the Copyright Act, no part may be reproduced by any process without written permission.   Enquiries should be made to the Author at djfmurphy@dodo.com.au.

Murphy, David 1938 –

Organic Growing with Worms

ISBN 0-9579091-0-02

Also by David Murphy

Earthworms in Australia

The Wisdom in Soil


Photography, except where otherwise shown, Margaret Murphy.

 Author's Note


I would like to thank a few people.  The first is my wife Margaret.

Then, (not in any order) Robby Watt, Clive Edwards, Neil Inall, Peter Cundall, Peter Ellyard, Ron Hall, Peter Rabbidge, Des Ferrow, John Buckerfield, Tim Parsons, Patrick Murphy, Jack Payne, Anton Barton, Richard Murphy, Coby Thompson, Peter O’Neill, Chris Carroll, John Sabine, Kevin Wilkinson, Neil Fauser, James Elder, Ursula Murphy, Glen Stephenson, and Toby Bainbridge, all of whom had an influence on me and this book’s content, often without knowing it, but nevertheless making their contributions.

There are a few others who I specifically invited to make a contribution but who did not take up the opportunity.   They could and should have contributed and the book may have been the better for it.  When you read this you will know who you are, so don’t complain to me that you weren’t included or maybe I didn’t report you quite correctly.

I apologise for the fact that I may jump from Imperial measurements - inches, feet, pounds etc - to metric - kilograms, metres and so on, and back.  It is because the example I am quoting is from a time prior to adoption of the Metric system in Australia, or an American example which would be in Imperial and should be faithfully reproduced.

 I also use "s" where my American friends use "z".   This is because as an Australian, I recognise that we speak the correct version of the Queen's English, where they speak a strange Americanised version (they would probably write Americanized) .  

No apology for that though.                                                                                  



“The future depends on what we do in the present”.

So spoke Mahatma Gandhi around 70 years ago.

The great thing about time is that the present is always with us.  If our forebears mucked up their present, we can learn from their mistakes and fix it in our present.

We need to understand that our present is a particularly critical one in Earth’s history. How we behave now decides the quality of mankind’s future. The Global Warming Greenhouse is not an if or maybe and there are no lifeboats.  It’s a bitter reality and the question is :- ”How bitter will the reality be ?”

Worms can sweeten this bitterness.

Of the problems facing this world of ours, two of the major ones are that we don’t recycle our organic wastes and our agricultural soils are severely degraded.  Both of these problems are man-made, the one by laziness, foolish opportunism and expediency; the other by interfering in the natural order in a foolish, short-sighted fashion.  By fixing the first we provide a partial solution to the other.   

Rarely understood is that by causing our agricultural soils to degrade and to lose their structure, a huge amount of carbon dioxide has been displaced from the soil into the atmosphere, where it forms part of the Greenhouse phenomenon.

Worms can be pivotal in correcting these problems, and in using them to do that, you can make a major contribution to stopping the Greenhouse Clock.  

Worms played a major role in establishing a fertile Greenhouse-free world; they can play an equally major role in re-establishing it.

Worms are Masters of Organic Growing; they are Masters of Soil Fertility; they are Masters of Organic Waste Recycling. 

Very broadly, there are two types of worms.  Compost worms which are the link in recycling organic waste into the soil and Earth worms, which are the renewers of fertility in a complex soil ecosystem. All life on our Planet, relies on the soil of the Earth.

Soil fertility and waste recycling are closely linked in the natural cycle of life. But; of all the animals on this planet, we alone are the ones whose wastes are not made available as the food of other, lesser, animals down the food chain.

Remember the old jingle “Every flea upon it’s back, has another flea to bite him and upon that flea, another flea, and so ad infinitem !”  That’s the way it was in nature with waste disposal until we came along and broke the cycle.  We stuff it in plastic bags and bury it where it will create a variety of poisions.

By recycling with worms – becoming worm farmers and farming with worms (which are quite different concepts) – people can play their part in returning our organic wastes to the natural order in environmental preservation, softening the severity of the Greenhouse.

We can solve the man-made problems !

In 1881, Charles Darwin wrote “Of all animals, few have contributed so much to the development of the world, as we know it, as these lowly organised creatures”. The really great thing about truth, is that it stands the test of time. Nothing has changed since 1881, and that statement is just as true now as it was then.

The book Organic Growing with Worms tells how to establish a worm farming (vermiculture) business on a starting stock of only a few thousand worms. What you are reading now isa small part of it.

However, it is not a book confined to worm farming but, perhaps more importantly, its message is to uncover some of the benefits of farming with worms - definitely not the same thing. The nature and history of earth worms has been to contribute to the provision of productive soil, and by constant recycling of nature’s wastes, renewing soil fertility, century after century.

We humans see ourselves as being at the top of the food chain and we have sought to divorce ourselves from it, as not being part of it, not recycling our “wastes”, spurning the natural order, using and abusing, manipulating nature, thinking our superior intelligence conferred a God-given right to ignore the fragile ecology in which we live. To refashion nature to our way, to change millions of years of established order in a few short lifetimes.  But the ecology in which we live is an ancient and totally enclosed system.  If we were to continue our rapacious lifestyle unchecked, our planet would become uninhabitable and we would self-destruct. We can’t just move next door - our neighboring planets don’t support life as we know it. As we trash this place, we have to live in it ! We really have to work more respectfully with Mother Nature. But, we need to do this fairly quickly if we want to avoid stern punishment.

Worms form an essential part of an ecological system which provided the framework in which our environment evolved.  “The Land” is the very pivot of a healthy and life sustaining environment.  We have the opportunity to undo some of the damage we have done, even to partially restore this environment without necessarily going broke in the process.

By understanding and using earth worms intelligently, by going along with them, and fostering them, but only as a component of a wider regime of changes, these incredible creatures can provide the means of restoring health to the land. This can be achieved simultaneously with us continuing to earn our living from the land, but at reduced cost and decreased labor input.

Earth worms used to be vital to the very survival of humans.  When our ancestors were making their way in the world, spreading out to new lands, in history long past, it was the incidence of worms in the soil which dictated their migratory routes and settlements, because often only worm‑populated soils were sufficiently fertile to produce the food necessary to sustain life.

It would be true to say that it was worms which decided where many of the major cities of the world would be built, because it was usually on the better land, the land with worms in it, that people settled, and it was from these small settlements that the major cities grew ‑ covering our best land.  This pattern of development continues and more and more of the better land goes down under bitumen and concrete, year after year.  As we become more and more dependent on the farming of marginal land and in order to maintain the food production needed to sustain life as we have come to know it, this marginal land gets flogged harder and harder.

We have displayed a very cavalier attitude to “The Land”. Many of us forget that without good renewably fertile soil, our economies will collapse. We will starve. Over the last 100 years we have made short sighted and radical changes to our treatment of the land, but most particularly about the time directly after the second world war. A little less eager would have been better !  The Mohikan Indians, before instituting any change, considered first, how this change would affect the next seven generations of their people.   What a contrast to our view of How is this going to affect this year’s profit & loss statement ?, or How will this affect my chances of being re-elected in two or three years ? Or very often this might make the Bank Manager happy !

To boost soil productivity we have developed and vigorously used farming methods which have destroyed the soil ecology and structure, pouring on synthesised fertilisers year after year, more and more.  At first, these practices paid off, because the synthesised fertilisers were applied to already fertile soil, but the soil has been in decline ever since.

More recently, in some recognition of the errors of our recent past, the words “sustainable fertility” have become commonly used. To me, they portray an idealistic concept and the biological equivalent of perpetual motion, or financially like an inexhaustible bank account.  It doesn’t happen. To take out, you have to put in ! The resource must be renewed periodically.  Therefore I don’t use “sustainable” fertility and instead use “naturally renewable”, a feature provided by earth worms

                                                                                                                       AN OLD FARMER’S COMMON SENSE

An old farmer once said to me: ‘Used to be that the only test needed to  see if the soil was good was to walk on it. If it was soft and springy beneath your feet, it was good, because it had worms in it.  That land would be good land and would always grow good crops’.

How can you argue against that sort of logic ?  It’s a well established fact that if you have worms in your soil, then there can’t be much wrong with it and it will be productive. In fact, if there were more of the appropriate worms in the soils of the world, much of the content of this book would be unnecessary. Farmers would be better off and the need for manufactured fertilizers would be greatly reduced – even eliminated.

Really, none of this is new, and everybody knows it. That being so, then why has it become necessary to promote earth worms ? Why is it that we have to go a good country mile to find pasture that is soft and springy beneath our feet ? Why is it now necessary to educate people, farmers and home gardeners alike, to the benefits which earth worms can bring ?

The reason is that we have been educated to the “necessary” use of manufactured fertilisers to make our soils productive. Unfortunately, this greater productivity is frequently short-lived and farmers increasingly find that, to achieve a profitable result, they have to use more and more fertilisers. They find themselves on a treadmill.

The fact that the soils of the world were fertile for millions of years, back beyond our recorded history, when manufactured fertilisers didn’t exist, seems to have been overlooked. We have been led to believe that we can work the soils better than nature. Many aspects of this belief are currently shown as being far from the truth.

Unfortunately for worms, they don’t have a Public Relations team.   They don’t have a lobby group.  They are diminutive little creatures which do their work silently and out of sight.  They’re not hi‑tech.   Their work represents no great breakthrough for science or industry.   They’re good for fishing, but....

The truth is, worms are excellent for fishing, but fishing isn’t all they’re good for.   There’s a lot more to worms than that !

Dry land salinity is seen by most people to be the most serious form of land degradation, but this is not so. It is possibly the most evident given the clearly visible creeping cancer because of the dead plants and the white salt encrustation.

The real culprit in the degraded agricultural land problem is loss of soil structure.  For example, in Australia for every dollar which dryland salinity costs in lost agricultural production, loss of soil structure costs $212. (Source: “Regreening Australia,” CSIRO Occasional paper No.3) Richard Eckersley). 

So severe is this loss of structure that on occasions New Zealand glaciers are tinged pink with Australian inland soil !  But, Australia is not an isolated example. The same is true of the monocultured agricultural soils of America and the entire world.

The task of refurbishing these soils is massive but it can be achieved with time and dedication. Every farmer needs to involve himself and work to reincorporate vegetative matter into the soil so that organic life can return, bringing with it that vital soil restructuring. Worms, their activity and their products can play a leading role in this project !

Worms can do more than help in restructuring degraded agricultural land.   Through this book you will discover how worms can help develop a beautiful and abundant garden for you; make money for you; how they can improve soil productivity; and, also importantly, how they can be significant in developing solutions to some of our society’s most serious environmental problems.

However, try not to lose sight of the fact that worms should not be looked upon as an independently operating super organism. They are a part of an incredibly interrelated and complex system, sequential links of which rely unequivocally on each other for survival. Take out one link, and the survival of the links on either side will be threatened. Indeed, ultimately they will collapse because their lifeline has been interrupted.  A ripple effect will go up and down the chain, so that ultimately, the whole chain will disappear.  But, even though it is an incredibly complex organism, once the soil biota has been destroyed, restoration can be achieved. It is not an easy job, but don’t lose heart.   It can be done if you, personally, do your bit   


It is interesting to note how the increasing wealth and sophistication of mankind affects the environment.

It took 2 million years for the population of the world to reach one billion.  Those of us born before 1950 have seen more population growth over the following fifty years than occurred in the preceding 4 million years. On Monday July 19, 1999 the world’s population reached six billion. It hit seven billion on October 31, 2011, barely 2 years later.   After that, the rate begins to slow though because eight billion won't show until 2025 and nine by 2045.    Dr. David Suzuki speculates that probably the world’s population will ultimately stabilise at around 10 billion.   Go to http://www.worldometers.info/world-population/ and watch the Birth Clock – it’s almost frightening ! 

These population increases occur mainly in seaboard cities and as they occur, more land is required on which the extra numbers can build their houses. (To calculate how long it will take for a doubling of population, divide the percentage increase into seventy).  Of this rapidly increasing world population, a high proportion is also increasing in wealth. As wealth increases mankind develops more sophisticated tastes and demands a more varied diet.  The wealthy portion looks to add meat.

Up to now grain made up a substantial portion of the world diet - mainly rice. 50% of the world’s grain production is rice and 95% of that is eaten in the country of production.  One kilo of grain eaten required one kilo of grain produced.  But to add meat to the diet, the formula changes.

If we want to eat a kilo of chicken, we must feed out five and a half kilos of grain.  A kilo of pork requires just short of nine kilos of grain and a kilo of beef, fifteen.  To get that beef onto the family dinner table takes over nine thousand litres of water per kilo ! (That includes processing as well as growing). A dairy cow takes around 120 litres per day !

So, our rapidly increasing, more wealthy population demands more food to be produced which requires more land from a shrinking availability which is also diminishing in its ability to yield harvest.   That’s a one way street if ever there was one ! Countries of small total land area are particularly affected by the population explosion.  A good example is Japan.  Over the past 30 years Japan has lost half of its total cropland and relies more and more on imported food.

Every year, in Australia, as much as 75 billion tonnes of topsoil are washed into the sea as a result of unsustainable farming, which equates to the loss of around 25 million acres of productive land.  Watch a river flowing by, note the colour of the water and realize that you’re watching millions of tons of topsoil on it’s way to the sea !  As a result, we can maintain current levels of food production only with the application of phosphate and other fertilisers, but phosphate reserves are likely to be exhausted well before the end of this century.  Forty per cent of the world's food is produced with the help of irrigation; some of the key aquifers are already running dry as a result of overuse.   Bores in The great Artesian Basin in Australia used to send a jet of water high into the air.  Now those same bores have to be pumped. (Source:Guardian/UK>http://commondreams.org/views02/1231-01.htm)

Increasingly we demand more from the land than it can give and the end result is destruction of the means of production. Soil structure is ravaged by constant additions of synthesised fertiliser. Common amongst these is urea which is used as a means of pumping nitrogen into the soil in a steroidal fashion. Just what disastrous effect this has on soil structure can be assessed by the knowledge that urea was used during World War 11 for the quick construction of air strips on Pacific islands.

It was used to destroy vegetation and compact the soil.  It was used to destroy the soil biota and structure ! Now it is used as fertiliser ! Come On !  What’s happened to the brains ?!   Maybe urea is not applied to agriculture at the same rate as then, but what about the buildup of resultant acidic salts over time ?

Even in our refined, learned and sophisticated society, at a time in our history where we know so much, we continue to display the hunter gatherer mentality.  Having destroyed land or consumed it for housing, we move on to subjugate more. We clear more land. We slash and burn forest, rain forest and scrub.

This is in addition to the three million hectares cleared each year, just for firewood !

Don’t forget also, that the best land is already gone, buried underneath the concrete and asphalt we know so well.  The new land opened up is constantly less able to meet the demands of an increasingly hungry society.

Our existence is no longer a cycle.   Mankind is the only animal which does not utilise its waste to invigorate and support another form of life.   We live by straight line consumption and it is absolutely not sustainable !  We harvest our agricultural land to feed our cities and that’s where the food cycle stops !

The organic waste from cities is denied access by useful life forms. It is buried in such a way that it is deliberately made to be anaerobic in bags of plastic film.  It is treated in such a way that it contributes materially to our destruction.  By burying organic waste in landfill tips, over time, a high proportion of the carbon - the most prolific element in life forms - is converted to methane gas which will percolate up through the tip capping into the atmosphere. There it works to warm our planet. That very same carbon should/could be used to rejuvenate our soil !

In soil, carbon creates life.  In landfill tips it creates poison !

In spite of this knowledge being known by all governments, (even by Primary School children) there are still government employees actually paid to plan, build and operate landfill tips for organic waste !

Some readers will be commenting mentally ‘But that methane is being tapped off and burned in industry’ and they would be right ! But methane extraction is only successful at extracting at best 60%.  The first 20% (when it is developing and accumulating) and the last 20% (when it is diminishing), cannot be extracted economically. It 's deliberately allowed to escape to the atmosphere.

This is the only living planet we know of.  The only one blessed with life sustaining water and a predominantly temperate climate. It was the combination of these factors that saw the present life forms evolve - us and what supports us.  It is paradoxical that we, the most sophisticated and intelligent of these life forms now threaten the existence of the very fundamental life sustaining system - that of the soil.

The old story about flogging a dead horse is very aptly applied to our soils - globally. But this horse isn’t quite dead yet. Certainly, if we don’t stop flogging, it will die. It will become sand and blow away. But; unlike a dead horse, soil can be rejuvenated.  But, do we have to wait until we are in an extreme global food crisis before we act decisively ?   Please stop for a moment and give this concept some good logical thought.

Did you know that for every one kilogram of wheat produced, because of the total loss of soil structure, the aggregates and biota, no less than seven kilograms of topsoil is permanently lost ? We commit more firmly each year to farming the subsoil.

Waiting to fix the problem until we are in crisis is exactly like waiting until you have lung cancer before you stop smoking.  But, the decline in soil health can be reversed and the death avoided. All it needs is common sense and respect for ourselves and subsequent generations.

For once, let’s be proactive instead of reactive !

A good example of being proactive is “Tandou Farm” in central New South Wales, Australia.  Tandou is in an 8” rainfall, fierce sunlight zone, and draws its water from the Menindee Lakes complex.

Tandou is a property of 200,000 acres, 44,000 acres of which is irrigated.  Having respect for the scarce resources of the land in which they live, the Management of Tandou have installed a drip irrigation system. Underground drippers ! Tandou laid 3000 miles of underground irrigation drippers !  At present the underground dripper system serves an area of 2000 hectares but is being extended as costs permit.   The result is that in spite of the huge area irrigated, the amount of water drawn off by Tandou is equivalent to only 100mm potential loss to surface evaporation from the Menindee Lakes. Compare this to the 1500mm actually evaporated from the lake surface every year !

All of Tandou’s organic wastes are composted professionally on site by qualified operatives, sent from Australia to be trained in America.   Between 3,000 and 5,000 tons of compost are produced annually, depending on the productivity of the year.   The compost is used on site to enrich the soil.

It is this type of forward thinking by the users of our natural resources which has to become dominant in the way we utilise our waste resources.  We have to stop flogging this poor planet of ours and revert to the natural means, to the Master, the Earthworm, and his workmates, to revive our lands and to produce our food stuffs.

The foregoing is a reprint from Organic Growing with Worms by David Murphy.  For more go to www.organicgrowingwithworms.com.au

A little extra to show where worms actually fit in the picture. . . . . .

In the download you have just read, I refer to the importance of a microbial population in the soil. In fact, without bacteria, there would be no soil !  Soil is made up of small to minute particles of rock, ground small during the last ice age and degraded organic matter.   Without bacteria, no degradation of the organic matter.  No soil !    The greatest vector for producing bacteria and distributing them in soil is earthworms.  Everything in these writings, short or long eventually points back to worms.  John N. Parle, a Research Scientist of the Department of Agriculture, based in Hamilton New Zealand 1963 published “Microorganisms in the Intestines of Earthworms” and showed that he had found a total population in Lumbricus terristris of 474 billion soil benevolent bacteria living in the gut. But, later research has shown that that figure may have been understated by a factor of 50. Multiply that out and then try and picture that number of bacteria in your mind !

Parle also discovered (1959) that because of the presence of worms in the soil, the number of bacteria per gram exceeded 25,000,000 !  To really learn what it’s all about you should buy yourself your copy of Organic Growing with Worms at the website.

Worm Tea – What it’s All About 

I prefer to call this product Vermicast Solution and Enriched Vermicast Solution, but everybody else calls it Worm Tea so I yield to the majority, not because they're right but because I can't be bothered to try and change them. There are probably as many recipes to make worm tea as there are worms in a tin.  I find 5% solid vermicast by volume a sufficient base.  That is to say, 5 litres (or pints) of solid vermicast to 100 litres (or pints) of pure water.  By measure; not weight.  In my case, I use rain water from our roof which is as pure as you can get without going to distilled water.  The roof  is coated with a membrane, the gutters, downpipes and tanks PVC, so there is no hydrolysis and the water effectively pure.

You know of course that you must use tanks of inert material – once again so that there is no hydrolysis.  If you used zincalumed or galvanised tanks for example, your solution will be (maybe heavily) polluted with Zn ions which could have a harmful effect in certain situations.    But you probably all know that. 

If you want tea with a long shelf life, then you simply steep a bag or stocking (see below) of casting in pure clean water and give it a good stirring.    The micros will come into solution as will the amino acids and other plant growth stimulators - the auxins, cytokinins, gibberellins etc.   Your population of oxygen-demanding microfauna will be low, say 30,000 per gram of solution and so, the product will keep 30, 60 days, maybe more.   The story changes however if you want a high population.

I tie the vermicast into balls 50 - 75mm diameter in ladies stockings and suspend them in the solution.  Bigger volumes require bigger or more balls etc, but still no more than 5% of solid vermicast.    Be sure also that thenvermicast is fresh, not aged.   Then I use a submersible pump, and arrange the discharge pipe in the tank in such a way that it delivers to the surface and makes as much splashing as you can, simultaneously seting up a swirl so that I have mixing and aerating combined.   Splashing is a very effective means of dissolving oxygen in water.   These days good quality stainless steel submersible, solids passing pumps, are not very expensive.   That's just one way of doing it - there are many others - and they all seem to work.   Don't be discouraged by any big words and mystique surrounding the construction of these brewers.    Just remember, all you have to do is dissolve oxygen in water to support an increasing population.

The purpose of this whole exercise is dual.   A very secondary purpose is to liberate the soluble minerals from the solid vermicast. Secondary because these minerals are there only in traces and not significant.  The primary purpose is to provide a means by which soil and plant benevolent micros, particularly bacteria, can be exponentially increased.   

Now, as your bacterial population increases, they need to be sustained, both in “breathing” and in feeding.  The splashing of the pump usually provides enough oxygen entrainment but you can add air from an air pump if you wish.   Can’t do any harm and can only benefit.  If you do this, introduce the air at the pump as it sucks in the water, so that it is swirled and mixed thoroughly into the water by the impeller and then held inside the delivery pipe where more air is dissolved into the water.   BUT; you need to be a little careful here, if you introduce too much air in relation to the volume of water, you can cause the pump to cavitate.   If it does, you should hear this because cavitating pumps are very noisy, so you may need to fit a valve to your air line so that you can restrict your air flow if you need.   Be guided by your ear.   If you hear a vibrating sort of noise, then reduce the air flow further until the noise goes.  A cavitating pump won’t last long.  

So, you’re giving your bacteria plenty of oxygen.  Now you’ve got to feed them.   Bacteria are the richest source of nitrogen on the planet with a Carbon:Nitrogen ratio of 5:1 and you're setting out to make a nitrogen (very) rich solution !  So, feeding efficiently, you need a soluble feed with a C:N also of 5:1.  The cheapest source of soluble carbon is black strap molasses and the most prolific source of Nitrogen is urea.    Now, I know organic growers will probably bristle at the mention of the word, but we are using the urea to make bacterial food, not to act as fertiliser, and the formula of the manufactured urea is exactly the same as naturally formed urea which is CN(NH2)2.





If your “Organic Principles” won’t allow you to use the urea, just use the molasses on its own.  The system will work less rapidly, but it will still work, with the bacteria trapping nitrogen from the air (which is 78% N) by the action of bacteria designed to do that.  They are called azotobacters and if yu're relying on them, you will have to aerate longer.  I can't suggest how much longer. Dr. Thomas Barrett never worried about it and he made plenty of "tea'.   If you don't know of him, Google him.   He wrote "Harnessing the Earthworm".

By this method, in one example, benevolent bacteria in a solution, after 24 hours aeration/mixing, were increased from 32,000cfu to 360,000,000cfu per gram of solution (cfu = colony forming units). (See Page 110 of Organic Growing with Worms).   This is what you’re after in making the tea or solution – plenty of mobile, life boosting nitrogen-rich bacteria !    If your solution is loaded with 5:1 food when you apply it, then the bacteria go into the soil, taking their lunch box with them.   They have the opportunity to enter the soil, to soak down to the roots, and even to continue increasing their numbers while their food lasts.  But then, when the food cuts out, they start to die off.   That’s when the benefit starts to show.   When they die, they decompose to their component parts, basically just nitrogen and carbon. This is natural fertilisation at its supercharged best !

The nitrogen is taken by nitrifying bacteria in the soil and converted to nitrite - NO2,  then others convert the nitrite to nitrate - NO3, the form in which nitrogen can be taken up by plants. (This is a very small snapshot of the complexity of a soil biota). The carbon is released into the soil as carbon dioxide CO2.   Some of this is absorbed by the moisture in the soil, making carbonic acid, pH around 6.5 - 6.8 or so, which helps to regulate the Ph of the soil at around neutral. 

The rest of the CO2 percolates up through the soil and as it escapes most is captured by the stomata on the underside of plant leaves.   They are there for that reason and evolved in that position when the organic matter OM of soil was much higher than it is today - around 20% and higher - and the atmospheric CO2 - much higher than it is today.  

It’s worth adding here that most of our food plants are known as sub-optimal photosynthesisers.  Simply put, they're equipped to photosynthesise much more than they do, but they are not able achieve their full potential because there is insufficient CO2 to allow it.  They evolved during a time when atmospheric CO2 was at much higher levels than it is today, as much as 1000 parts per million (ppm).  This is why as atmospheric CO2 increases, crop yields do too but without an increase in chemical fertiliser application.  The higher the level of CO2 in the atmosphere, the better will be the yield of our crops.   

Back to our tea !  As with Biodynamics BD 500 (see pages 124 - 131 of Organic Growing with Worms), teas need to be applied out of direct sunlight, or on a cloudy day or at night.  This enables those bacteria which do not fall on soil, but on plant leaves, to establish a UV barrier before the sun comes out to kill them (Ingham, personal communication).   The tea is loaded with beneficial bacteria and food, so they can very densely colonise leaf surfaces.   One special member of the bacteria family are actinomycetes, special because they will also produce an incredible range of antibiotics, like Streptomyces, which then produce a further sub-species of antibiotics such as Erythromycin, Neomycin, Tetracycline and Cefoxitin.




Teas also have the ability to ward off flying pests, micro and macro.  Have you ever seen white butterflies (they are butterflies, not moths) land on brassicas recently sprayed with worm tea (enriched with 5:1 food or not) ?  They don’t !  They fly away.   I don’t know why.   Vermicast tea is odourless and tasteless, but it has that effect.

In application by spray, you will more than likely kill the bacteria if you use high pressures.  It’s not the pressure which kills them, it’s the sudden change of pressure as they leave the nozzle and enter the free atmosphere.  An instantaneous pressure change from say, 50psi to 15 may cause their bodies to burst.  They are tender littler creatures.  You can pump them out but make it a low pressure spray.  On my veggie patch I like to apply tea with a rose on a watering can, but that's very low numbers.  One customer used to apply it by helicopter, but still at low poressure.   On page 120 of Organic Growing with Worms there’s an illustration of a farmer (Davo Davidson) applying tea to his property through a low pressure fire fighting pump.  You can see that the rig he's using is not sophistocated or expensive and on the web page Home Page there's a big spray rig putting it out, but again at low presssure.   It’s just a question of what is most suitable to do the area you are working.  By using worm products like enriched tea, Davo has doubled the carrying capacity of his farm in under 3 years and the worm population of his soil has gone from close to zero to over 400/m2. It will only get better.

Now, the question of shelf life.   As mentioned above, if you make only a weak solution, you will have a much longer shelf life than the enriched tea described above.   Ideally, the enriched tea should be prepared just before it's to be used - just like Biodynamics. If you store your enriched tea in a stoppered container for too long, it will quickly use up the oxygen.  Bacteria use oxygen just as we do - to sustain life - and they need it in the same concentration that we do - around 20% of the atmosphere.    “Too long" may be as short as overnight if your population is high.   Kept refrigerated will be much better - it will stay aerobic longer.  

Most bacteria are facultative, which means they can change their hats according to their environment. Today they are aerobic, and the tea, sweet smelling.  Overnight, they use up the oxygen but they don't die.  They simply change their hats and become anaerobic and stink !  People say “It was sweet last night, I don’t know where the bad ones came from !”.  Well, they were there all the time, just waiting for the chance to ambush you !! 

So, what do you do now with several gallons of stink ?    Well, you can put the air back in by bubbling or pumping/splashing.  They’ll very quickly change their hats back to aerobic again.   Or you can just apply it as if it was still a sweet smelling brew.  Be sure you have no near neighbours though !

The stinking tea that falls on the soil is still full of bacteria, and even though it is now anaerobic.  The bacteria still have a C:N ratio of 5:1 and are still the richest source of Nitrogen on the planet.  Exposed to the air, they very quickly do a Marx Brothers hat change and return to aerobic.  Tea is an exceptionally robust product, intended to be aerobic and will always return to aerobic on exposure to air. 

Dilution.    You can dilute enriched tea with pure water, virtually as much as you like.  Go to 100 times – not 100%, that’s only two times -  1 litre or gallon made up to 100 litres of gallons by the addition of more water.  It will still work.   I have often seen 50 times used and it always worked well.  There’s a colour photograph of pasture at my place sprayed with 50 times diluted (plate 9) on the fourth of the colour pages in Organic Growing with Worms.  Look at that pic, compare and wonder at the power of this amazing product ! 

A little tip.    Once you have made your first brew, the dissolved minerals are so unimportant they are not worthy of consideration in these brews.  It's the benevolent bacteria and other microfauna and flora you want, even more so than the cytokinins, giberellins etc and amino acids.   This means that once you have made up one brew, you can then simply keep adding water and food, keeping it aerated and agitated.  The areation and agitation doesn't have to be any more than soldiers marking time.   Just use a small aquarium aerator to keep the air bubbling in your brew.  If you find you can detect an unpleasant odour, add another aerator (It all depends on how many gallons/litres you have).  That will be adequate to maintain a Master Brew, from which you can keep drawing supply.  If you want to sell at weekend Farmers Markets, and you have a trailer, you can make your Master Brew in one of those 1000L tanks so common these days and tow it to market in your trailer, aerating with an aquarium bubbler powered from your car electrics.  If you have some empty bottles, customers love to see their brew freshly drawn from the Master and soon, they'll turn up at market with their own empty container to be filled from your Master Brew.  It’s a good way to establish a rapport and long term relationship with your customers.  

There’s been quite a bit written and claimed about putting the bacteria to sleep, or into suspended animation as part of these magical liquid bio-brews.    Well, pigs might fly also !   I suppose it may be possible, but I haven’t seen it yet.    Maybe they hypnotise them !   All I’ve seen so far is smoke & mirrors, mumbo jumbo and bullshit !  Pay no attention and give them no credit. Above all, don’t feel that you’re not doing it right because you’re unable to do this yourself.    Nobody can !  You’re not at fault and you’re not failing in your efforts at becoming a competent maker/marketer of worm products !    As I’ve written above, the bacteria will change hats with bewildering speed so don’t worry about it.  People who make those claims are only weak marketers who think they have to surround their products with mastery (I think I'm smarter than you but I'm really a dill syndrome) and mystery.   It’s a clear sign that they don’t know their products and therefore lack confidence because the truth is much more exciting than their rubbish. 

One thing you can be sure of.  You will never kill or harm any plant with worm tea.   In fact, the reverse is the case.   I have applied it liberally to trees that looked entirely dead, dead, dead.  And some recovered.  One was a 150 year old beautiful Lemon Scented Magnolia in our front garden, which fell victim to a 10 year drought.   We couldn’t water anything properly because we had very little water in our tanks and everything in the garden died from the front to the back.  The Magnolia looked absolutely stark with only a few leaves left on it and if you bent a branch it just snapped as dead ones do.  After the rain finally came, some trees recovered, but not this one.   It’s actually a wetlands tree, and we’re in a low rainfall area, so it's not really in the right environment.  I made up 100 litres of enriched tea, and over a week diluted it 50 times and pumped it into the ground around the tree.  Within a fortnight it was showing leaf buds and now 6 years later is about 80% fully recovered.  I don’t think it’ll get any better.   I tried the same system on a couple of others, but, alas, the magic was not powerful enough !

I could keep writing for more pages and still not cover every question you may have.    There are no hard and fast rules with this product and it's very hard to make mistakes.    Remember it can go from aerobic to anaerobic to aerobic in conditions which you might expect all the bacterias to be killed, but it will still be good and you won't get sporulation.     

The process description above is good for 20 gallons or litres to 5000 and I have customers who have made batches of even more. Farmers use it to fertigate - use the diluted product to irrigate their vines and crops - and the result is clear. Just have confidence in it, make and use it any way you like and you'll be right.   A customer in South Africa rang me one night to very jubilantly tell me she had followed the instructions in my book and had trebled her millet yield in the first year !    Doubling of crops is common.  If you have more questions you can use gthe communicator on the Home Page.  Don't forget to include your email address and I'll get back to you without delay.     You can also use This email address is being protected from spambots. You need JavaScript enabled to view it.©