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What the Roots Looked Like on The Compost Tea Garden Growth Experiment

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Root Results of Compost Manure Tea Experiment

Last month I posted the “Compost Tea Garden Growth Experiment” and was shocked by the number of emails I got over it with questions, maniacal rantings, and angry comments. I promised the peeps who wrote me that I would answer their questions in a blog post. So here you go –


Question – There is no legitimate proof that compost tea really works, so your claims are ridiculous.
Answer – I am a “Doubting Thomas” and did not believe the manure tea would work. So I was doing the test to prove it wrong as much as to prove it right and was not expecting the final result.

Question – This was not a “scientific study” done in the lab so your results are meaningless.
Answer – You are correct. This was NOT a scientific study. I am an ordinary gardener trying the manure tea in my regular old garden under regular old conditions. I am not a scientist, nor did I make pretenses of being one. This was an experiment. I showed the results – I don’t think they were meaningless. I do wish, however, that several colleges and/or scientific labs would do scientific studies on this as I feel it would be informational for the horticultural and gardening world at large. For the love of gawd – someone does a scientific study. I think it’s a good idea.

Question – Annie Haven is your friend, so you skewed the results to be good for her.
Answer – Yep. Annie Haven, the owner of Haven Brand Manure Tea is my friend. But here’s the deal – when she shipped me her Moo Poo Tea to test, we had a special agreement that I would be totally and 100% honest about the results of the experiment. If her manure tea did not work for me, then I would publish the results. If it did work for me, then I would publish the results. Honesty in the results was all that mattered. I did not skew any results. The results are the results. The end.

Question – Why do this? It takes too much time and I can’t see you doing it with the large garden you have.
Answer – I cannot put manure tea on every plant in my garden, but if I were worried about some special vegetables or other types of plants that needed a little extra “umph”, then I think this might be a solution. This is not for everyone but would be interesting to try if you are curious about how you might help amend the soil for a plant.

Each container held 3 plants;

  1. Bonnie Plants Rosemary
  2. Purple Flash Ornamental Pepper
  3. Superbells Pomegranate Punch Calibrachoa

Question – This cannot be true. You obviously watered the manure tea container more than the others.
Answer – I did not water any plants more. I watered them exactly the same. I even measured the water in the container to make sure. When I put the manure tea on the plant, I would also water the other plants with plain water. I watered them all exactly the same.

Question – Hey Shawna Coronado, you piss me off. You tell us there’s supposed to be strengthened roots, but then never even show us the damned roots. What kind of blogger are you?
Answer – To that point, I’m a blogger who’s imperfect. So you can be ticked off all you like; sometimes I forget to show you every detail. With your question in mind, I went out and took photos of the plant roots. The photos of the roots are on this post and the container parameters are below.

What was different in each container –

  1. Container #1 had 1/3 of a Jobes Organic Spike placed in the middle of the container between the plant roots. It was watered once per week.
  2. Container #2 was watered once per week like the others, however, it was watered with Haven Brand Manure Tea once per week while the others were just given water.
  3. Container #3 had nothing additional whatsoever given to it and was watered once per week.

Below are close-up photos of the three different root systems up close after the experiment. Judge for yourself.

Root Results of Compost Manure Tea Experiment Organic Fertilizer Container
Root Results of Compost Manure Tea Experiment Compost Tea Container
Root Results

There you have the amended results for the story I posted on the “Compost Tea Garden Growth Experiment”. I hope seeing the roots will help you make a better decision about whether you want to try manure tea in your garden. My recommendation is for you to TRY THE TEST and check it out — do the experiment at home yourself. If you try the product in as fair a test as you can create, perhaps you can see if you want to use it again in the future. Meanwhile, I hope some colleges and scientific institutions will also try the test as well and study the results for all of us. Happy Gardening!

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  1. Farmers have been using manure for thousands of years. Free, easily obtainable fertilizer. How much proof do you need?

    Annie is a cattle rancher (and a friend of mine, too) reusing the waste that would otherwise pollute the waters on and around her property. I often wondered why more ranchers did not sell manure.

    I learned about manure and compost tea in my Master Gardening classes taught by University of Maryland staff. I had heard about it before from experienced gardeners.

    Your experiment only confirmed the results I see in my garden. Do not let the vocal minority dissuade you.

  2. I have used Annie’s product and found similar results. The roots tell the story.

    I am shocked that people would write such emails. It is fine to disagree or have issue but the way people speak to each other is appalling.

    Thanks you for addressing them in such a respectful professional manner.

  3. People,people,people. Lets remain calm. The commercial establishment has you believing that in order to try anything new you must own a laboratory. Thomas Jefferson,you know , ex president of the u.s.,and Ben Franklin,past statesman of the U.S. were not trained scientists but both did some pretty good science experiments with pretty good results. All one can do is try and look at the results. If the results are good we try it on a larger scale. When I ask a gardener whatt they do to make their roses beautiful I don’t don’t ask for clinical test results. I take their word for it and try it myself. P.S. shawna. You responded Very professionally to some ridiculous people.

  4. It’s okay for people not to agree with me. I encourage honest and frank conversation. I just wish angry mobs with pitch forks would stop storming the front garden. ::grin::

    I’m KIDDING! But some days it sure feels like that. It would be nice if people were nice to one another instead of hateful. 🙂


  5. The apple orchard I picked from this year also uses manure tea on their trees. The owners have an agreement with their neighbor…the neighbor removes all the fallen apples to feed their horses and then the orchard owner takes the manure and makes tea for the trees. WIN for everyone concerned including the consumer.

  6. Shawna, I just stumbled onto your blog post and wanted to thank you for doing the compost tea experiment. As to the disrespectful questions and comments, that’s exactly what they are – disrespectful. Every one of us living on this planet, whether animal, vegetable or mineral is a scientist; and we are part of the experiment of Life. I don’t get angry at the disrespectful, I feel very sad for them. Then people like you appear and hope for a sustainable world is replenished. Thank you.

  7. I suspect those messages are from some of your detractors, same ones who have a problem with your fence…. seriously…. glad I wasn’t raised to be like that, and cannot imagine what makes people so sick they have to bash others! Good grief!

  8. Thanks Debbie, but I think their primary concern is scientific validity and I truly identify with and understand that concern. They want proof. I’m not a scientist. SO – I think the answer to this is more scientists and gardeners need to test this if they are concerned about the results.

    In all tests there are failures and successes, so we shall see what happens. Expecting me to be a scientific expert in home garden conditions is an unreasonable one.

    Thanks for your words!

  9. I have a BS in horticulture and even though this experiment is not strictly scientific, it is a valid and valuable experiment.

    I encourage you, and all others, to continue with well designed and well thought out experiments.

    May I recommend that you test the manure tea against a water soluble commercial fertilizer? I think that would be a great test and would be more of an apples to apples trial.

  10. absolutley agree!!! some of the published comments are just rude…good experiment Shawna!!! Good product Annie!!!
    Shawna had the insight to to the experiment…and the courage to share it…those mean people who have been so critical should perhaps do their own experiment to see what happens for them
    hugs to you all!

  11. Amazing that people would actually get ANGRY about compost tea. It works by the way, there is so many other things one can get angry about for heavens sake

  12. Scott – You can click above on the blue letters that say “Haven Brand Manure Tea” and it will take you to the tea website.


  13. Ummm, not sure where everyone is reading the “ugly, angry, disrespectful, sick, idiotic, abusive, negative, hateful” comments. I saw 13 comments, all but one of which said “…very good, thanks, excellent…”.

    My own question is, What is the difference between “soil amendment” and “soil conditioner”?

  14. Hi Janet –

    I think they’re talking about the questions that were asked in the questions and answers above.

    In answer to your soil amendment VS soil conditioner question – these terms are often interchangeable. Sometimes a soil conditioner is a product used for loosening the soil and/or improving the soil structure and microbial activity (all the little microbes and natural creatures that exist in the soil which make up the soil and promote root development in a plant).

    Soil amendments might (or might not) have a blend of organic or chemical-based fertilizers to encourage plant growth. Additionally, soils quite often need some sort of help in order to improve moisture retention, provide aeration, increase drainage, and supply organic matter to the root systems of plants and a soil amendment dug into the soil system might help.

    Either way, I prefer using organic soil amendments/conditioners whenever possible and try not to use a chemical unless it’s the last possible resort to an issue I might have. Building the soil structure of your garden beds is important for building strong plants.

  15. Hi Shawna:

    Do you think if I bought a bag of manure from the big box store and made my own manure tea, it would be the same? Thank you for your response.

  16. I can believe people asked you all those mean questions.
    The experiment was very helpful and I liked your cool answering those questions…

    Great blog by the way

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