Does Compost Tea Work? 

My Great Grandfather used to have us kids go out into the pasture and collect sunbaked cow patties which he would soak in pails of rain water and then after a few days he would then water the garden with it. He always had a bountiful garden

Does anyone else find the comments discussion almost as interesting as the video itself? It really says a lot about your videos and your viewers. Keep up the great work Stephen.

Scientific testing aside, my compost tea experience was amazing. It does make plants healthy and strong to take all the nutrients they need from whatever soil they have in various parts of my garden. After I’ve introduced compost tea to my garden, I forgot about plant diseases. If I want to boost some blooms, I can always use a bit of a synthetic fertilizers, but only as a “dessert”, never as the “main course”. I avoid stressing my plants out with synthetic fertilizers. I opt for healthy root systems.

This is a highly underrated channel. I love all the experimenting you do. I often do my own but it's nice to see other peoples experiments to save time and share ideas. Thanks for these.

Interesting. I always use Compost Tea not as a "fertilizer" but to assist my plants in absorbing nutrients already present in the soil and to increase soil biology

Compost tea feeds the soil and worms which feed your plants. And the best thing about it is that ill never overfeed so you can use it everyday. It's easy to make why not use it.

Wouldn’t it be easier to just have two sets of plants. Feed one set the tea. And gauge the results? Rather than assume you or anyone else truly know the infinite number of bacterial interactions in plants or the beneficial effect of that bacteria in the food and humans who consume them.

Had a feeling the results would end up like this. You are the only one doing testing like this and I sure do appreciate it you efforts.

Nice one Stephen. Am a big fan of making up a tea as a way to spread compost around rather than brewing for increased benefits. Really interested in seeing if the commercial tea brews are as good as a basic home made one ;) Cheers mate.

Great results Stephen! I love that u have a lab close by to test all of these myths. I steered away from AACT a while back because I didn't see the benefit of it if I already use plenty of compost in my garden. I agree with Patrick, compost and mulch can provide all the nutrients and beneficial bacteria your plants need. I'm looking forward to your follow up video!

This is the chanel I'll view if I want good solid, scienfiic results. Thanks for all your hard work.

I have tried compost tea, both foliar, and in the soil, and I could not see any difference! So I would say your tests are completely accurate, Stephen!

I would say that you have made a few errors in your statements and experiments. What you describe as a compost extract is actually a non-aerated compost tea, referred to as NCT in scientific research. Compost extract or Liquid Compost Extract (LCE) are both utilized for primarily microbial content and NOT nutrient content, although as you discovered there is some residual nutrient value. If my friend Jeff has stated this in the book you said you sourced then he just got it wrong. So you know LCE is a fast extract process. e.g. we do 50 gallons in 5 minutes and use 4 times the amount of compost used in CT. You are fixated on bacterial multiplication but that is only a portion of the microorganisms extracted and multiplied in aerated compost tea (ACT - the term AACT is 100% silly - google Microbe Organics) Depending upon your compost quality/activity and the quality of your bioreactor (CT maker) you should see increased levels of bacteria, archaea, flagellates and/or naked amoebae and fungal hyphae if present in your compost. You may see lots of youtube video data on the above mentioned resource. The general idea for nutrient cycling provided via compost tea is to extract & multiply a good ratio volume and diversity of bacteria/archaea and flagellates &/or naked amoebae (protozoa). This generally requires about 36 hours of running a quality design bioreactor (brewer) and providing adequate feedstock if needed (I agree that kelp is a poor option). As the protozoa feed on the bacteria/archaea they utilize only 10 to 60% of the nutrient value for their own sustenance. The other 40 to 90% is discharged in plant available (bio-available) ionic form. This is how a nutrient boost is provided to the roots of the plants. There are hypotheses about disease suppression utilizing CT but I'm not getting into that here. Testing: You have noted, accurately, that plate culture testing is not a good choice for this application. Probably the nutrient testing is not either but I don't think you mentioned the extraction process used by the lab. Many of these are inaccurate when researching sequestered nutrients. A better procedure would have direct microscopy and microbial count. Bioreactor; I've often stated there is no such thing as bad compost tea but it is easy to make it better. I would improve your brewer by using a pump outputting around 1 CFM (or use several small pumps). I would run air with diffuser into the extraction bag and consider running for 36 hours but 48 isn't terrible. Once agitation is improved you could use up to 0.5% molasses by volume. I would say that putting the compost directly into the water and stir with whathaveyou would produce superior results to what you have used. Keep on learning:)

Also the main purpose for compost tea isnt its fertilizing abilities but the billions of benificial microbes that will battle diseases on the plants and make them and your soil thrive!!!

I would love to see a result of a well brewed tea vs. the simple tea you brewed up. I think the CFU is important but so is a break down of the diversity of species within the soil. I think you should see what types of fungi and bacteria are native to your compost and see what compost tea can do to increase other species. Another point for compost tea is foliar application to help reduce powdery mildew and other pathogens. Another consideration is that compost being time released has its limitations to the ppm it can release to the plants at any given time where as compost teas are for instant gratification and a boost to microbial life. I not sure that this simple test sways me.. I think more research needs to be done

Living by the sea gives me access to seaweed. The shop bought seaweed products are very expensive(I know they are concentrated a lot but still). After soaking it for a month with leaf mulch it has made the richest looking juice that I can’t wait to use to enrich my nans garden.

This video is funny. Each formula for compost tea is different and has vastly different effects. This is because the types of bacteria and fungus grown differ greatly based on not only the compost and food sources, but the concentration of nutrients used, the temperature and the amount of time it is grown. Aeration is usually used to culture aerobic fungi. The effect of growing a high fungal tea is to provide chitin to chitin degrading bacteria. This produces the compound Chitisan which activates the plant self defense mechanism producing class 2 and 4 chitinases. Chitinase degrades the cell wall of pathogenic fungi and insects. In high concentrations it will also cause a plant to put more energy into fruiting. Adding sugars can produce organic acids which can dramatically effect the solubility of the nutrients in the soil. The types of acids created will vary depending on the types of bacteria present, the nutrient in the media and available oxygen. The function of compost tea is determined by the type of organisms grown.

MICROBIAL (not only bacterial) DIVERSITY (not only abundance) is a well established factor that plays a role in plant physiology (nutrition, stress resistance, and disease protection) as well as in soil functioning (nutrient cycling, disease controll...). You are not addressing those issues, though you cannot talk about compost teas as a whole. Why wouldn't you make a real-world (not only lab' counts) test and see its effect on (at least one variety of) plant health or yield throughout an entire growing season? That would be a real contribution to knowledge that many gardeners and agricultural scientists would be delighted with :)

I used compost tea last year and apart from the smell I did not notice any difference. Thanks Stephen for highlighting the subject and your analysis too. Will be interested to watch the replacement.

So very interesting. I was going to buy a pump and stone to try this method. YOU are so amazing in your approach to gardening. I look forward to your videos. I did make the tea with just the soaking from wormcastings. It looks like I might just as well just add the wormcastings to top layer of the soil and be done with it. Thanks for all the research. Can't wait for the next episode.

My belief (not scientifically tested) is that it can help jump start good soil life when turning a degraded area into a garden. After that initial "boost", I think just compost and mulch would do the trick just fine. Even with that belief, I probably would just go with compost and mulch and let nature do it's thing. I appreciate you taking the time to consider these practices and challenging them in a scientific way. Put on your armor every time you take on one of these challenges! There are many people who will defend their methods quite aggressively! :) You are doing great work my friend.

Thanks so much! Really appreciate your efford to try to bring some clarity regarding all tips that are around! I simply use compost on top as a mulch and then let my watering, rain and worms do the rest! This seems to work very nice! Simplicity is also a factor for me! Looking forward to your next video🌸

The difference is that compost tea allows you to spread the same amount of compost over a wider area because the volume becomes larger due to the addition of gallons of water.

What temperature where they at? I would also point out that as an individual who has no investment in whether or not this works, and is just gathering info, I find the counter arguments in this video to be more swaying. I will watch part 2 , but I think the experiments need more work.

You need a minimum of 0.5 CFM per gallon to produce a decent batch of compost tea. However, as much as 0.8 CFM per gallon is recommended. A common fallacy is that an aquarium pump will suffice - this is far from the truth. The whisperer air pump you used isn't even adequate for brewing a cup of compost tea. This is why your lab results are so poor. Proper analysis of compost tea is done through a visual count through a microscope and not by plate count. True compost tea is an microbial inoculant. That being said, if certain food sources are added they will produce a fertilizer value in the end.

the passive broths (popular in biodynamics) require daily stir it ups for its short oxigenization instead of turning anaerobic.

Your videos are very well done and super informative. I am sure a lot of people are not going to like these results as they live by the compost tea but proof is proof. Thanks for taking the time to do the experiment and sharing your findings.

breath taking video!

I've always thought long and complicated compost tea brewing methods was an unnecessary complication. Creating a habitat around your plants that harbors beneficial bacterial means any method of introducing bacteria should end up with similar results after several days in the new environment. Bacteria would flourish in a good environment and struggle in a harsh one. It does seem like if your compost tea hits equilibrium that you could evaporate the water to produce an organic concentrate. Besides killing off the bacteria there could be other losses as the water evaporates, and many times there are better methods for fertilizing your plants, but it could be a good option for specific uses. Either way, the results are very informative. Thanks for the great videos!

I'm a lapsed lab tech. I think it's worth pointing out that the bacteria in a rainwater barrel are likely very different from the bacteria in the ground that produce fertilizing compounds, although there is a lot of overlap. So counting CFU's with a method that counts these different kinds of bacteria equally will not show whether either kind of bacteria is more relevant to the plants than the other. Also, I think the total count of bacteria is somewhat unhelpful. The plants don't eat the bacteria, but the biproducts generated by the bacteria. And the amount of these biproducts depends more on the input of nutrients for the bacteria than the count of the bacteria, since the bacteria will grow exponentially if given abundant nutrients. So it makes no sense to me to increase the total amount of bacteria, since the kind of bacteria that will grow in sugary water are not necessarily the kind that want to make fertilizer for plants, and the ones that like sugary water can potentially compete against the useful bacteria, rendering the solution much less useful as a fertilizer. My suggestion would be to get the compost tea to the soil regularly or not too long after extracting it from the compost, so that the bacteria that live in the soil can maintain a healthy population "in situ", since that's where they're needed (and since there will be less competition from water-borne bacteria). Intentionally increasing the amount of unknown bacteria just seems to risk ruining the batch or even risking adding a disease risk to your soil, unless you do something to ensure that the right kind of bacteria grow in it. (like adding cultures or chemicals, although that defeats the purpose)

My understanding is that the reason for aeration is to promote the growth of beneficial bacteria and suppress the growth of anaerobic e-coli. Your experiment did not differentiate between these two bacteria types. A good real- world test would be to grow tomato plants in sand and see the difference in health/ growth rates between your organic 20-20-20, aerobic tea and anaerobic tea. Thanks for the video!

The problem I find in your test is that you used a limited number of sources for your tea. For example my tea has bat guano, kelp, alfalfa meal, yeast, worm castings and humus. And I use not a cheap aquarium pump, but a commercial pump with 750 gallon per hour flow. Now if you compare say my tea in diversity and nutrients. It would blow your tea out of the water and now you have something to compare to synthetic fertilizer. Compost with molasses is simply not enough diversity to contend with synthetic ferts. I mean it's like a synthetic fertilizer only adding phosphate but leaving out nitrogen and micro nutrients. I mean look on the bottle do they only use 2 sources of nutrients like you did with your tea?

Results will vary depending on the compost source imo. If you are using a steer or chicken manure in your compost, then I would say you will raise your risk of pathogens and risk of E coli. Vegan sourced composts should not have these variables. The majority of AACT I brew uses humus or premium vegan fed worm castings as the base of the brew outside of carb sources. Carb sources will play a major role as well, depending what monosaccharide or polysaccharides are available to the colonies to feed on. The types of beneficial bacteria and fungus are vast and from what I have learned will have different effects from different plant types. Glomus, rhizopgon, bacillus, trichoderma, scleroderma, suillus, laccaria, pisolithus are some of the different bacteria and fungus that I would have been curious to see CFU and propagules per cc counts to see what kind of biodiversity and numbers in testing, not to mention the nematode and protozoa content. The length of brew time will shrink biodiversity but increase population size of certain colonies that are more dominant. In my experience, microbial and fungal inoculation to soil plays a big difference in taste, yield, essential oil production, nutrient uptake and plant health. These break down complex compounds for better biological assimilation, and having higher strength in numbers to fight off pathogens and unwanted bacterias and fungus in the soil. Foliar feeding produces a biofilm that protects in the same way and can hinder downy mold hypae from spreading and keep away some hard and soft bodied pests (bacillus thuringiensis "BT" that we know kills caterpillars). Steeping compost without air will produce anaerobic colonies which may have bad numbers of the wrong bacteria and I would not suggest using that method. I am no mycologist, I manage a chain of hydroponic stores and have been gardening for 10 years and I am just speaking from the experience I have.

I would agree, a good hummus, top-dressed by a thoroughly composted material, is the best way to go. The important thing to learn here, is WHY bacteria is beneficial, and how it acts as the middle-man between nutrients and plant roots.

An older but useful video. There is a "concern" that compost breaks down. My friend said she uses tea to continue providing tea to give a "bump" to the original compost, but I'm not sure how you'd test that. Another note is that rain washes many of the nutrients from your compost. My friend built his compost bed on concrete with roof over the top. A small amount of the diverted rain was piped onto the compost pile. They were also trying to figure a way to capture the runoff and distribute it over their garden and yard. I assume that's similar to dairy farms where waste is liquified and spread over acres of growing plants. I did take advantage of runoff, one season, from a friend's rabbit farm where he captured a "slurry" of the runoff from the manure pile. (I filled a number of 35 gallon drums with this dense slurry as an easy way to boost 1.5 acres of grass.)

The easiest strategy I recommend is to spread compost as a top dressing and then water or let the rain water your plants. This process will leach the nutrients into your plants roots. As grandma always says "No muss, No Fuss".

in the spring you can 'jump start' soil bacteria by simply using plain old table sugar & water. You probably don't need to do this more than once or twice in the spring. Don't go crazy with the sugar either. Leads to mold and other undesirable things. Biggest benefits of compost tea is the minerals and trace elements you add back into the soil. Also, the microscopic bits in compost tea are 'bioavailable' to soil bacteria. The soil bacteria is what breaks things down for plants to use. Aeration adds precious oxygen to the tea. This is why fresh rain water is best. It already is saturated with oxygen. Cold rain water holds more oxygen than warm rain water. Using synthetic nitrogen can sterilize the soil of bacteria. The addition of mycorrhizal fungi can be of value.

Last summer, me and my husband went to a local lake that had been trained. On the shores were millions of tiny shells. I collected a bag of shells and added them to the garden, with the idea they would add calcium overtime.

You dont make compost extraction with water. You make a plant extract with it and then airly activate it. This is a wierd test youre doing

Interesting results, Stephen. I think the replacement strategy is to just use compost and mulch.

There are so many flaws associated with this video, they are almost too many to mention. This demonstrates a fundamental lack of understanding of soil microbiology and the science underlying the principles of compost, compost extracts and compost teas.

Personally thought the object of compost tea and worm teas is not for the nutrients but for adding more diversity of old growth forest fungi as well as locally sourced microbes around your garden. To give your soil a more balanced biology which will result in less weeds and a more fruit filled harvest. Just starting to play with "knf" and "jadam" which uses no synthetic nutrients but does use plant extracts, as well as compost teas. Thus far I can't complain it's allot cheaper this way to grow food that's for sure

I love your experiments. But according to Dr. Elaine Ingham, bacteria count on Petri dish isn't a good way to exam the microorganism in it, so they suggest use microscope for counting. Some of their claims just sound too good to be true. Few examples, 1. forest, bush, and grassland has different fungi bacteria counts, so if you raise the fungi, bacteria ratio, you'll solve the weed problem. 2. every plants has it's suitable ratio between bacteria and fungi, if you want to grow more trees, better use fungi dominant compost tea 3. by having predator nematodes, protozoa in compost or compost tea will increase nutrients cycles, and can reduce plants' illness 4. a poor managed land can be revived with just one perfect balanced compost tea applying on it 5. nutrients in compost tea might not increase, but microorganism in compost tea will absorb insoluble nutrients, and add it to nutrients cycles Above are just few claims from compost Tea lovers. I love their romantic vision of one application to end all problems, but I couldn't totally buying that idea, bcs I don't have enough knowledge to know if what they say is true. that's why I love your channel so much I guess. the only channel put almighty rock dust into test on internet :D

So basically forget the tea brewing and rock dust ?! That's going to save me a lot of time and money lol !! I know juries not out yet in the tea but thanks for all the scientific work you put in !

Please do all the tests on the claims.. This is a science. I will follow up.

I live in the desert so rainwater is not an option for me. However, I do have slightly salty well water and slightly salty alkaline soil. I use home made compost, but made my garden a bit large for my compost production and have had to use several amendments to produce food. Over time I believe my garden will be able to produce food and compost to replenish the soil every year. I use extracted compost tea just to get more bang for my buck from the compost ( I can't aerate it due to being off grid). I am so grateful for your very informative videos because it helps me decide what I can do to improve my food production which is my goal. Thank you.

This video is remarkably thorough. Even the printed verbiage is thorough. I'm very impressed with this host and his channel. By employing the scientific method, reality may be revealed. Well done!

AACT is good to Kick-Start everything with newly built soil. After a while if the soil is full of micro-life and worms there is no need to do anything but Top-dress. Nice video well explained.

Synthethic fertilizers are no fun in home gardening although they might be better in the long run compost tea is just plain relaxing to brew at home knowing that youre using natural readily available ingredients and just watching and waiting for your very own batch of compost tea that you know you made according to your recipe. That is the very core of home gardening so whether it has a bunch of microbes or very little nutrients no synthetic fertilizers will ever deliver that awesome satisfaction of watering your plants or vegetables with your very own homemade batch of pure compost tea

But it does no harm, right? I've always used compost tea on stressed plants and seem to get great results. Is this a case of confirmation bias?

i want to start by saying first off thank you for taking time and resources and investing them into a study that you have been gracious enough to share with us. there are a few things wrong with this video, and it all starts with your basic premise, that compost tea was intended for a fertilizer, this is not true. the main benefit and intent with EWC tea is the beneficial microbes. Any fertilizer benefit that could be gained is more of an added perk that is not the original intent of the process. your statement is correct, that for the most part compost tea is pointless in a garden because the organisms already exist in the soil. however there are benefits under certain circumstances that the tea would be game changing. - when indoor or container gardening in situations where your soil either does not contain a useful population of beneficial microorganisms or the scales have "tipped" and there are an inordinate number of harmful microorganisms in your root zones. - hydroponic applications, where you have an infestation of harmful microorganisms (most commonly slimes) where a tea would have a limited benefit to host on and outnumber the harmful microorganisms. depending on your hydroponic methods the usefulness varies, but there is still an application. - regular gardening methods in which soil borne harmful microorganisms have gained a foothold in your plants root zones. in situations like these having a direct application method of distributing helpful microorganisms is beneficial. and again, the fact that the tea also contains a mild fertilizer is merely a perk, not the intention. i think that your main problem here is that you were basing your theory and understanding of tea on one book, and had not done enough research into what the tea is and why its used.

the experiment shows that 7 days (without bubbles) and bubble for 2 days produces the same result. I think I will just wait 7 days instead of bubbling 2 days straight.

An important detail is missed: bacteria do not release nutrient but simple store nutrients in their bodies. However, the nematodes and protozoa (each eats 10,000 bacteria per day) cause the nutrients to be released. One should test compost for protozoa and nematodes and can do that with a simple microscope that magnifies 400x.

From my research on compost tea it seems most home methods simply are not producing the real deal. The recipe for the tea and brewing time has to be tightly controlled and the end result has to be used within a short window. Constant monitoring is required or the batch is basically wasted. Without that tight control all that is happening is the spreading of water with compost in it which is basically a weak fertilizer as you discovered. One of the most common mistakes for brewing is not using a pump that moves enough air. The standard aquarium pump is not moving enough air in a 5 gallon bucket. You cannot use the gallon rating of a pump based on oxygenating water for fish. The oxygen needs are much higher for AACT. One of the often overlooked benefits of compost tea being brewed and applied correctly is the beneficial microorganisms attach to the plant at such a concentration that harmful disease organisms are essentially blocked out. This is why you will see compost tea used in organic agriculture as a disease preventative, but only if its brewed exactly right.

This video was fantastic and very informative! I look forward to your next video on the subject as I've never used compost tea and was considering making some to use this season.

You shattered my dreams of making compost tea for the first time. I was so excited lol.

I use comfrey tea and add compost to it. My plants love it!

Awesome video, great information. Appreciate what you're doing. Looking forward to the follow up vid.

Great Video Stephen, looking forward to the follow up.

I try to limit open buckets of water around here due to mosquitos( x 100, Zika). Dry compost only for me. Did my 1st oncamera video today! Officially joined the online gardening community!

Oxygen levels are too low in your buckets for bacteria and fungus to proliferate. I commonly see this issue when people are using air stone pumps. It would be interesting to see what would happen if you directly injected oxygen into a bucket for 72 hours that had been inoculated. There should be a very thick head at the top of your tea when it is finished much like what you would see on a beer. Also be sure to allow the chlorine to dissipate from the water for several days before you actually add compost or you will kill everything. The point of introducing fungus and bacteria to soil is to establish a mycorrizhal mesh and to fortify the soil with aerobic bacteria. Note, if you are using commercial fertilizer which is not organic you may be actually harming the bacteria and fungus which has established itself in the soil. Again, Compost tea lets you jump start a symbiotic relationship between fungus,bacteria, and plants roots. It is not a quick fix But rather a long-term investment for the health of your soil and plants

The microbiological testing results were only shown for a short amount of time. He mentioned that the level of microbes was at 12,000 cfu's/ml. it appeared to show that the results were actually greater than 12,000 cfu's/ml and at that dilution the plate was too numerous to count and was probably much greater than 12,000 cfu's/mL.

Interesting experiment ;) Was considering using compost tea purely to spray leafs of vegetables just heard it helps to prevent fungi diseases to colonize leafs, but couldn't find any proof that it actually works anywhere. I think teaming with microbes should be first book anyone who is interested in gardening should read.

Mineral-derived NPK plant foods (or synthetic in your words) are a fantastic tool for the garden. However, most gardeners do not know how much or how often to use such a tool which can give bottled NPK foods a bad name. Once again, great test!

I think the testing done was very limited to a small range. There has to be a reason why plants grow better with it

Clever Man...nice to hear actual results from your experriments.

i would love to see this revisited using my recipe

Okay, as I've posted a number of times on these sites, and can't speak for Canada, but water treatment/MUDs do NOT use chlorine anymore, they use chloramines, which is a chemical combo of chlorine and ammonia, not the chlorine gas which would disperse into the air. The only way to reduce this, and fluoride is using reverse osmosis. Virtually ALL water providers in The U.S. use chloramines now, I'm sorry to say.

Kudos for this presentation. The bottom line is that a tea made from compost by any means will not exceed what the compost one started with. BUT, what about a tea made from another organic source such as fresh grass clippings, comfrey leaves, stinging nettle, and kitchen vegetable waste? Unlike compost, these are not already broken down by bacteria, fungi, nematodes, or worms large and small. Will an aerobic tea made from these sources digest them, releasing their nutrients faster and more completely than composting them?

Lots of videos showing success using compost tea on RU-vid. Harvard University. A giant vegetable world record holder from Alaska. Several organic lawn companies. Different private gardeners. Elaine ingham has several videos on Vimeo talking about using compost around the world with great success. Look up Elaine and Georgia Organics on Vimeo. Unless they are all giving false information there is quite a bit of visual information it works.

Very good work - I appreciate your scientific approach. I use long-fermented anaerobic teas now. Wish I had a local lab - it would be worth analyzing. And... I subscribed. Keep it up!

The synthetic nutrients are also chelated, and readily available to the plants. The tea is not a fertilizer to feed the plants, the tea feeds the microbes. The tea has non chelated nutrients that need to be broken down (chelated) by the microbes which they trade to the plants for sugars that the plants produce via photosynthesis.

Thank-you for doing these garden science videos!! It is great to have some evidence for what we do in the backyard garden. So I guess compost tea was actually a way to save money for me because I was always applying it during watering times instead of just adding a bunch of new compost every year. I decided I don't like mulching as much as I thought I would because in springtime we get a lot of pill bugs that can also feed on the seedlings (yikes!). It'll be hard to give up the idea of compost extractions....! But it would sure save the effort :) I added a bunch of composted manure this year so I'll will try not to water with the compost tea and see how it goes.

phosphorous and potash are both minerals. The synthetic part of fertilizer is made from petroleum. Potash and nitrogen can easily wash out of the soil but phosphorous doesn't and can have too much if not used by the plant.

Great when greatly prepared. Like almost everything!

Great Testing.. You cover all the ares. Well Done. Would you still recommend compost if someone was growing in Plastic pots?

Subscribed! I appreciate a fellow Alberta-ian, and one who follows the scientific principles. Have you tried comparing the CFU of the rain water vs diluted compost, vs compost tea? I'd think the compost tea is way more bio active due to the aerobic bacteria and sugar.

I've always been happy using my own, homemade compost and worm castings from my worm farm. Never bothered with compost tea. Thanks, Stephen for another thoughtful and thought provoking video.

What do you think about the 95% of wasted water and nutrients in the soil? I'm most of the time using sub-irrigated containers to be sure nothing is wasted.

Great work Stephen! I'm super excited about this. Part of me was actually kind of hoping that you'd find that compost tea is everything they say it is and more but this is much more exciting cos I was considering making the investment in everything necessary for making aerated CT and now it sounds like I can keep cash in pocket. Woohoo! Looking forward to your next video. Looks like you've lost some weight. On purpose? Looking good bro!!

Not being an expert, but a user of the aact method. The question I have is that not all compost is made the same. So the quality of said compost , even using worm castings for aact which Is what I use could be different. But I can see your point that if the compost is good that the use of brewed tea might not be needed, but the issue goes on as we know many argue against your theory or tests.

True LIving Organics! Hot soil! LIving SOIL!! NO TILL! Cheers!

Great job. This video was everting I needed to know.

Stephen, I have read that using AACT as a foliar spray will protect against things like powdery mildew and such. Is this an effective practice?Thanks for another informative exploration.

Thank you. Compost Extraction seems slower but easier to do in bulk.

Interesting subject matter that definitely strikes deep into the nervous system of certain gardeners. I am curious to see what the results will be when the entire experiment is completed. Great job exploring a touchy subject.

I always thought that the tea was to help increase the microbial and bacterial numbers in the soil, which help the plant take up nutrients, not necessarily a food source for the plant

After learning healthy plants growth from NPK industries (NPK University RU-vids), I will experiment with my small garden (tropical). I understand that compost tea is more about cultivating beneficial bacteria and microbes in a liquid nutrients medium, and supplement to garden. Surely, the addition of compose tea is also adding nutrients to the soil. So I am saying compost tea has its merits.

Wow... with science, it shows proof that aerated "Compost Tea" is all hype. Its amazing that you went into the effort to send multiple samples to a lab.

compost tea is like real tea. I mean there is so many different types, so many recipes, so many flavors, and honestly.. soil science is a science in its self. I have a friend who has 400 acres in Iowa. Not a BIG farm but a pretty large farm. He isn't organic but does fertilize using the latest in technology. Guys come out and via GPS plot and sample the land. He gets a 20 page summary of the different aspects of his soil and he for the last few years has saturated his fertilizer over the whole of the farm, beans included. I like to take a pragmatic approach to things. Organic fertilizer breaks down to available vitamins and nutrients for plants. That is.. available to uptake on the ready. That is.. what mother nature has already broken down from the larger forms of what was once plant and nutrient matter.. so the new plant growth has it available as a food source to grow healthy. Honestly your results could be from what you decided to use. Look up Hydroponics and their laundry list of available product additives. Everything from Bat Guano to.. sea salt. A "1 product does all" approach is probably not going to be the best approach to your plants, root veg need a phosphorus rich fertilizer, where as a green heavy type needs a nitrogen heavy type.. etc. etc. I would not write off compost teas as junk or waste of money by any means. There is a science to it, and to grow the bacteria that you will then transfer to the soil, to eat what is in the soil, for them to breakdown the product your plants will uptake. That is probably the largest thing to take away from compost tea.. you are actually growing the organisms that you will transfer to the soil.. not so much what it is that you will gain solely from the tea. Molasses is actually a "dessert" and is supposed to be administered after the tea is getting older, and the food source has been diminished. Just like a fish Hydrolysate is not supposed to be administered to the plants foliage.. it is not bio-available, it actually needs the microbes to break it down, but is 1 step off of being bio-available.. you would add it to your compost tea within a half of a day of spraying it onto your crop soil. I don't have just "thinking" behind my thoughts, I have actually gone to school for horticulture and I am telling you that there is a LOT of dis-information out there.. even from retailers. That is why I started Kansas City Heirlooms & Organics. I figure it would be best to put the real information out there. Anyway just thought I would give you a heads up on everything and like anything it can be the test, not the results that have been why you came to the conclusion you came to.

You can also use an underground worm farm, it works very well when when your garden is mulched and you feed the farm. Cool video and thanks for sharing. Happy Gardening Marty Ware (from Australia)

At 3:42 you say "I have extreme reservations on the use of kelp in the garden" What do you mean? My wife and I have used kelp meal and soluble kelp in our garden for years, with great success..

I heard 36 hours is the max before it starts having a reverse effect.

Very informative. Thank you for taking the time to test this theory.🇨🇦 Lethbridge

Dr. Elaine Ingham. I would recommend you watch several hours of her findings.

Compost teas aren't designed to extract nutrients, but to grow soil microorganisms. A nutrient extract whether made from compost or manure is not a compost tea.

I've heard mixed things about bio char as well. figured I would test it myself. i didn't have a soil test or anything. but bio char can be used to grow in. made my own in my metal raised fire pit. directly under it is ash and nothing grows. but a circle around the ash is black char, with vigorous grass growth concentrated there. somehow a tomato seed got inside my fire pit (filled with bio char) and is growing in nothing but bio char. one thing we all can agree on is that no one really knows much about the complexity of healthy soil life and it's interconnected relationships. keep the field and lab tests going everybody.

Just an idea to run your bacterial test... get a bottle of humic acid like URB, do a table spoon of it per gallon of water with just water. Then another of URB with molasses or kelp and another of both (possibly) with no compost. Just a more controllable idea, and also a test I would like to see if you don’t mind 😅

Thanks so much Steven for simplifying things for me and my garden.

I mix grass and water. Sunflower leaves and water. Got several 4 month old gallons of tea from weeds