The Best Compost Tea Brewer On The Market
$65.00 – $172.00
There are tens of thousands of different species of microorganisms that have a huge part to play in the health of your garden.
They kill diseases, feed and protect plants, improve the soil, and perform a long list of other jobs.
In 2006, I was running my organic gardening business and learning that my clients’ gardens were deficient in proper biology.
And luckily I had just finished reading ‘The Compost Tea Brewing Manual’ and studying compost tea in general, and discovered the importance of bringing these important microorganisms back into the garden.
So I decided to try it. I started with the highly recommended KIS compost tea brewer – one of the first and still best tea brewers on the market (based on independent lab testing) – and I never looked back.
Even compost tea guru Elaine Ingham of Soil FoodWeb Inc. says the KIS brewers are among the best brewers:
“The KIS brewers are extremely easy to set up and use, very easy to clean, and make great teas by extracting all the species of bacteria, fungi, protists, and nematodes present in the compost into the tea. Using the right resources, the KIS brewer can get fantastic fungal biomass growing in their tea maker.
Using the KIS starter foods and compost, we have never seen the KIS brewer have a problem maintaining aeration. Even if “poor compost” has been used, where E.coli and other pathogens were in high numbers, these problem organisms have been dropped to less than detectable levels by the proper use of this machine.”
Dr. Elaine Ingham, Soil Microbiologist
“From the instant I got my KIS brewer, I knew it was going to be fun. The instructions were so simple that I set it up in about three minutes and turned it on before I went to bed. I used the tea in our greenhouse the very next morning (14 hours later instead of 12, but that was only because I slept in!). It was a fine looking brew with a great smell, good feel, and excellent color.
I was quite sure my plants would appreciate it and I couldn’t wait until the snow melted and I could get out and use the KIS-made compost tea on our gardens and lawns. Am I pleased with my KIS? Just try and take it away from me. Thanks for this important machine. It will change the world. I know it has changed the way we garden here in Alaska.”
Jeff Lowenfels, author of ‘Teaming With Microbes’
What Is Compost Tea?
The right side of this tree was sprayed only one time with compost tea from a KIS compost tea brewer, along with liquid fish fertilizer.
The leaves are so much more abundant, bigger and healthier on that side, actually hiding the cherries from view.
The purpose of compost tea is to reintroduce beneficial microorganisms into our gardens that ideally would be there in the first place, but often aren’t any more for many reasons.
As with mycorrhizal fungi, that includes past tilling, topsoil removal during construction, environmental pollution, pesticide/chemical fertilizer use, and so on.
Those microorganisms are largely responsible for the health of our plants. They help:
- Increase plant nutrient uptake, making your plants bigger and healthier
- Not only prevent plant disease but can even get rid of existing disease
- Increase water and nutrient retention in the soil, so your plants get more of both
- Breakdown toxins in the soil and on plant leaves
I mainly think about it as boosting plant health, which ultimately means more nutritious food and fewer pests.
Unlike SCD/EM, the tea is also a broad spectrum organic fertilizer of soluble nutrients that can be immediately used by both microorganisms and plants.
By the way, be sure to read the comparison to both SCD/EM and mycorrhizal fungi on the right side of the page.
Back to what compost tea is. To be clear, when I say compost tea, I mean the modern version, which is ‘aerated’ compost tea.
Some people even say ‘actively aerated’ compost tea, which means we use an air pump to aerate, not just a stick to stir the tea once in a while.
Compost tea traditionally meant compost that was left in a bucket for a few days and perhaps stirred a few times, and it can have some benefits, but a quality aerated compost tea with an air pump is going to be much more useful.
DIY Compost Tea Brewer
A lot of people want to make a diy compost tea brewer, and it’s certainly possible.
There are a lot of factors that affect tea quality, though, so if you want to make a good tea that brings in the big benefits, be prepared to do some lab testing and tweaking of your brewer to get it right.
But if you really enjoy tinkering and you have a bit of money to spend on lab testing, I could see that being fun even though you’ll end up paying more.
Most homemade compost tea brewers don’t cut it, so the most important advice I can give is to make sure you get a good air pump that pushes a lot of air – not a little aquarium pump like a lot of people on the internet suggest – that won’t make a tea that does much of anything.
The EcoPlus Commercial Air 5 is a great one, or even the Commercial Air 3 would be better than a little aquarium pump.
I figured out that it would actually be much more affordable to use a tea brewer that’s already been thoroughly tested, so that’s what I’ve always done.
So while I’ve played around with making my own brewer, I never did any testing because I already had a KIS brewer that was working great.
The KIS Compost Tea Brewer
They’ve recently changed the design of their brewer to something that’s more affordable.
It was designed by Tim Wilson and it’s called the Mini-Microbulator.
This brewer makes high-quality compost tea (well tested and documented), with a reliable air pump.
It takes about 36 hours to make a tea.
Here’s a video from Tad who makes these brewers in the U.S.
What Comes With The Compost Tea Brewer
This comes with the air pump and all of the tubing.
You have the option of getting it:
- Without a 5-gallon bucket and without brew kits, or
- With a 5-gallon bucket and 3 brew kits.
And on this page, you can also buy extra brew kits, which contain the compost and microbe foods (or you can use your own compost and foods if you want to experiment with your own recipes).
The nice thing about the kits, though, is that the quality of the compost is excellent. It’s actually a mix of Alaska humus, worm compost (vermicompost), and fungal compost.
The compost tea produced from these brewers has been tested in a lab with this specific compost and this specific food mix and it makes a great tea, so all you need to do is follow a few simple rules you will have a great compost tea.
FYI, the kits are derived from sulfate of potash magnesia (aka sul-po-mag or k-mag), feather meal, soymeal, cottonseed meal, mycorrhizal fungi, kelp, and alfalfa meal. It’s registered organic, so all non-GMO.
How To Make Compost Tea
Here’s a video from Tim Wilson, the designer of this brewer:
Here’s how to make compost tea.
Air is bubbled through a bucket of water that contains a bit of quality compost and other ingredients.
The bubbles pull the microorganisms off the compost (as otherwise they’re kind of glued on there) and also give air for the microorganisms to breathe.
That’s important because we want to create a compost tea of mostly air-breathing (aerobic) microorganisms, as they tend to be the beneficial ones for our organic gardens. Of course, there are some not-so-good aerobic microbes, too, but many more are good guys.
Then the other ingredients are foods like liquid kelp and liquid fish and molasses that feed the microorganisms and cause them to multiply like crazy.
When it’s done, we have a solution with trillions of beneficial mostly aerobic microorganisms that we can spray into the garden (maybe even quadrillions if you did a good job).
One reason this is useful is because while there’s often not enough compost to adequately cover the garden, compost tea goes a lot further.
So if you haven’t been using compost, compost tea is going to bring many of the same benefits, other than the organic matter.
But even more interesting is that we can spray compost tea right onto plant leaves where the microbes will feed them nutrients and protect them from disease – in fact, if you make a good tea and get your leaves covered fully, it will be very difficult for diseases to live there.
It can’t be marketed as controlling disease because it’s not a pesticide, but we have clear research showing that the microorganisms in good compost tea keep disease populations in check.
How To Use Compost Tea
A decent 5-gallon brew will cover an acre of garden, but even if you only have a tiny garden, you can spray the whole batch of compost tea and that will be even better – it’s impossible to overapply it.
It’s preferable NOT to use a hose-end sprayer for compost tea because the container is far too small and because we mostly want to use it undiluted (i.e. not mixed with more water) in order to get the maximum concentration of beneficial microorganisms on the leaf surfaces.
That’s where a different kind of sprayer comes in – either a backpack sprayer or one that sits on the ground. Here are links to 2 of my favorites:
1. Chapin – $130. Tad Hussey, who’s in charge of manufacturing the compost tea brewers on this page, recommends the Chapin 1949 concrete sprayer. Being made for concrete, it has big enough filters to allow beneficial fungi through. I recommend home users get this one.
2. Birchmeier – $250. This brand of sprayers can get expensive, but it’s one of the best on the market, so they don’t leak and break down as much as most other sprayers.
While Solo sprayers are popular among compost tea users, they have more problems when compared to the sprayers from Birchmeier.
But backpack sprayers aren’t generally designed for compost tea, so you’re going to want to strain the tea first. A 400-600 mesh size is the sweet spot for letting the microbes through without letting organic debris through. A paint strainer bag is one good way of doing this.
One other method that some people use successfully is to drop a sump pump – wrapped in a mesh bag – down into the tea after it’s done, attach a hose to it, and spray from there.
I think this is a great idea for a small garden but haven’t tried it. Sump pumps work pretty fast, so you’d need to be ready to shoot the tea quickly, and then ready to turn the pump off so it doesn’t burn out.
For application, the rule of thumb is 5 gallons per acre for each 6 feet in plant height. So if you have an acre of plants that are 12 feet tall, you would need 10 gallons of tea.
But most of us are just doing our backyards, so 5 gallons will be plenty. It’s impossible to over-apply it, so even if you only have 500 square feet, feel free to spray the whole thing out there.
I recommend using compost tea at least two times per year. I tend to go with three times, but you might make this your main thing and apply it monthly, and that would certainly be excellent, too.
Get It Here
$65.00 – $172.00
In summary, the tea from this compost tea brewer:
- Provides these main benefits: improved plant growth and nutrition, better soil structure/water-holding capacity/nutrient retention, decreased disease.
- Increases the diversity and number of highly beneficial microorganisms in your soil and on your plants.
- Is proven to be a high quality actively aerated tea.
As a free bonus when you order today, I’ll also enroll you in my online Compost Tea course.
Just choose your brewer and click ‘Add To Cart’ up above!
- I ship in the U.S. only. I ship 7 days a week.
- In the continental U.S., shipping is $15.
- All of my products have a 1 year 100% money-back guarantee.
- If you have a question about a product, leave it in the comment section below I'll try to respond within a few hours.
- Dry fertilizers and compost tea brewers ship separately so they will arrive on their own maybe a day or 2 apart from my other products.
- I send a percentage of every order to Thrive For Good and other similar organizations. They're working mostly in Africa to help communities grow organic, medicinal food for themselves, and then use the surplus food to generate income for themselves as well as feeding the orphans in their communities.
Free $25 Bonus When You Buy Today
When you buy one of these brewers, you get enrolled in my online Compost Tea course.
It’s an introductory course, a nice little bit of info on compost tea. My main goal is to show you how to make good tea and how to apply it.
The course includes 11 videos totaling about 50 minutes.
Forgive me if I missed it, but with this brewer do I still add nettles/comfry etc or just the ingredients in the packets?
Just the ingredients in the packets for this one. A little bit of nettle/comfry could certainly be added for the benefits they bring, but I wouldn’t want to deviate too much from the standard recipe.
Ok thanks – what’s the best plan then to turn my bucketfuls of nettle&comfry into sweet compost tea???
You can make a non-aerated ‘herbal tea’ as I show here in the 2nd half of this video: https://www.smilinggardener.com/organic-fertilizers/homemade-fertilizer/
!do you have an online class? can you share the link? thanks!
Hi Sandy, I’ll open it up for enrolment for a few days in October.
What are your thoughts on Stihl sprayers for compost tea?
Could be good. In general, we want the tea to go through as little filtering as possible, so not too many fine screens and small holes to go through – just enough so that the sprayer doesn’t clog.
I had picked up the solo sprayer from Lee Valley last summer and it was a bit flimsy, so I returned it. I thought about getting the Stihl sprayer but I wasn’t sure if there was too much pressure or that the nozzle was not going the be appropriate for compost tea, and only useful for chemicals. Is there anything you need to do to modify the Birchmeier to spray compost tea?
Some people go so far as to take out the filters (which means you’ll want to strain your tea very well), or replace them with 400 micron filters from a hardware store in order to make sure more of the biology gets through – takes a bit of work, but not too bad if you have the parts diagram that comes with the machine. It’s worth the effort.
Another sprayer I really like is the Chapin 1949 Concrete Sprayer. Their customer service is awesome and it’s designed to handle large particulate. We use ours around the Farm all the time.
Thanks Tad – good to know.
Is a sprayer necessary in applying the compost tea? Can I just use an old-fashioned watering can?
Absolutely, a watering can even has the advantage of causing less harm to the microbes. In order to apply it to the leaves, it’s nice if it has an attachment to turn the water into a coarse mist/fine shower.
Am confused. Does the green brewing kit come with 1 set of product to make tea once? Is it 3 different product to mix? And your website says for $39 you can make 3 more? How can that be if one is $300? Don’t know terminology well yet, so struggling to understand. Seems to me that sometimes brewer kit means the bucket & accessories; sometimes it refers to the product to make the tea. so new to this
You’re right Diane, the word ‘kit’ does apply to both, so it’s possible that I’ve used it to refer to both. When you buy the $300 brewer, you get the air pump, the bucket and all of the tubing that pumps the air through the water. It also comes with 3 ‘kits’ that each contain the right amount of good compost and microbe foods to brew a batch of tea.The extra kits can be purchased when you’ve done your first 3 brews and want to make more, although some people elect to use their own compost and microbe foods at that point, using their own recipe such as this one: https://www.smilinggardener.com/soil-food-web/compost-tea-recipe/
Hi! I received the brewer a few days ago. Very excited to begin! Still cold here, though. 20F to 45F.
Instructions say to use it indoors, so I need to find a spot for it. I have no shed, barn or garage available but there is a small basement, and spare room/studio.
I want to do a test run with water only. Sound reasonable? I want to check noise levels before deciding which space to set up.
You can certainly use it outdoors when the weather’s good, although if your neighbors are close, they may not want to listen to it, although covering the whole thing with a big box does help. And yes, no problem testing with water only – you can even leave the water in the bucket for when you’re ready to do the real thing.
Just bought your tea brewer kit. Instructions say: Add Simplici-Tea, compost, and molasses–how much molasses do I add? No quantity is given! Also, inside the paper bag is a mesh bag of compost (I assume), and a separate ziplock bag–what is inside the ziplock bag, is it the Simplici-Tea? The ziplock bag is not labeled, and the outer paper bag does not mention Simplicity-Tea, only that it contains ‘Compost & Microbe Catalyst Ingredients’. Your labeling and instructions could use a few edits to clear up these questions!
To recap my questions:
1) How much molasses do I add?
2) Is the Simpici-Tea inside the ziplock bag, and do I put that inside the mesh bag or loose in the water for brewing? If loose in water, won’t that clog my sprayer?
Thanks for your help in brewing tea with my new Simplici-Tea Compost Tea Brewer.
Hi Sharon, I emailed the manufacturer and he says:
I’ll need to revisit the label and get it updated. Not sure how that got on there. They do not need to use molasses if they bought our tea brewing kit. It has everything included in it. Basically the steps are the following:
1. Make sure you have dechlorinated water or have treated the water.
2. Drop in the mesh bag that contains the compost (biology) with the brewer running.
3. Sprinkle in the contents of the ziplock bag.
Apologies for any confusion, let me know if I can answer any other questions.
Phil, item 3 in your response….should that be to sprinkle the contents of the ziplock bag?
You don’t have a slug problem. You have a duck deficiency. Bill Mollison
Yes, fixed, thank you!
Thank you for your response. I will ignore the Compost Tea Brewer’s instruction sheet (#7) that says to add molasses, and assume that the contents inside the ziplock bag is the ‘starter food’.
Glad to hear that the manufacturer will revisit his instruction sheet and bag labeling to clear up confusing information.
Thanks for all the useful info, I’ll be getting my kit soon.
I am interested in purchasing the micro – brewer plus the BioAg, Sea Minerals Fertilizer and the Humic Acids powder…my intention (please correct me if I’m totally wasting my resources) was to use some of my compost with these items and brew up a spray for the 80’x40′ garden before the winter weather hits – I’m in the process of applying all of my leaves and spreading some of my old grass clippings around (not nearly enough). I was also thinking to purchase some alfalfa meal.
Does this sound like a good plan? I’m hoping to do a no-till garden – but I’m just not sure what to do with the weeds in there now.
Any advice would be seriously appreciated!
Yep, that’s a great plan. As for the weeds, it depends on the weeds. Some weeds will find their way up through 6″ of leaves and some won’t. Regardless, they’re a lot easier to pull when you have a thick mulch. And then the tea helps improve the soil in multiple ways, eventually making it less hospitable for some weeds.
I am just about to use the mix of products I bought from you last year, but I am afraid that the molasses will bring ants to my plants, can you tell me if I am correct, also I am doing compost the way I saw in the internet, with a paint bucket buried on the ground with openings for the worms to decomposed the stuff; the first one I took out was a little bit smelly and I don’t know if that is normal. The products I bought from you were molasses the Bio and the seaweed. I will appreciated your advise about my concerns.
It’s possible that the molasses could attract ants. It also sometimes repels ants. You could try it on one plant and wait 2 days to see if anything happens.
I’ve never done that method of composting but it’s not surprising that it’s smelly. If you mix in some dry, carbon-rich materials (like leaves/straw/sawdust/newspaper/cardboard) with the food scraps before you put out the bucket, that will help. And spray the scraps with the Bio Ag, too, as those organisms can really help with bad smells.
I forgot to mentioned that the water I use for my plants is rain water, if I want to use compost tea, can I use the water from the rain?
Rainwater is usually great for compost tea. That said, some rainwater gets contaminated from roofs that are made with toxic materials so you need to consider that.
I’ve used the 3 gallon pump sprayers to spray compost tea, but they are cumbersome to use, and tend to clog frequently. So lately, I’ve been using a hose sprayer from Ortho with the 8 oz setting, which I believe is a 16 to 1 dilution. I can thus water my plants and apply compost tea fertilizer at the same time. The one downside is disconnecting and refilling the sprayer a couple of dozen times, but since I’m accomplishing watering and fertilizing at the same time, it’s not that bad.
What are the pluses and minuses with this method?
Thanks & Regards,
The main downside is that, when spraying the leaves, each leaf can only hold X amount of liquid, so you may be getting something like 16X fewer microorganisms populating the leaf surfaces.
The other downside is, if the hose is using chlorinated water, that’s not ideal for the microbes in the tea, although I don’t recall seeing data on this. Certainly, we need to brew our teas without chlorinated water but I’m not so sure about how impactful it is using chlorinated water in a hose-end sprayer to distribute the tea.
The upside is that hose-end sprayers make application (and cleanup) so much easier, and if that’s what allows you to get your tea out there, perhaps even more frequently, it may be a worthwhile compromise.
I have written you twice. About a year ago I responded to a customers question about the possibility of an air pump being too strong for a small batch of compost tea (5 gal.).
You weren’t really sure.And since I had just read about the possibility of the microbes being shredded, ( on Tim Wilson’s site ). I thought it would be a nice gesture to provide that info.
I never received any sort of reply and in fact my post was deleted.Since this is where I posted my response, I now see that the question was deleted also.
I was only trying to be helpful. I enjoy your site, and the knowledge that you share. I’m quite grateful for!
My question now is, that I wrote you again yesterday this time with several questions I knew that you could help me with. I believe there were 5 questions. Along with info about what I ‘be been doing in my garden and trying to help my 83 year old Mother with hers.
I do intend on trying several of the products that you offer. I’m still waiting on my stimulus check (I made a mistake filing but it’s all been corrected now) too much information but fund a currently a little tight.
Anyway, I realize that it takes time to answer and respond to all the questions, and feedback that you receive. But once again it appears that my text has been deleted. I don’t understand and I was hoping you could explain it to me. I included my last name in my last text. I’m not going to do that again. I wasn’t thinking about it being published. But I doubt that you have any other folks with my name. And of course you have my email.
I could really use your help. I’m very grateful for you and your site. I’ve learned a lot and continue to learn more every day. Thank you, for your time.
I responded to your question last year. It was on a different post. And I’ve now responded briefly to your question from 2 days ago, on that post. Questions don’t get posted publicly until I respond to them (it’s to prevent spam). Good luck with your tea and AEM 🙂
I would like to use my solo backpack sprayer to apply the brewed compost tea using your brewer. You suggested to repalce the solo filter so that more particles can go through. I looked at the solo manual and don’t see any filter part. Only the removable filter basket at the top. Is that what you meant?
I was probably talking about the Birchmeier filter – some people remove it after they’ve strained the tea really well. I’m not sure about Solo.
Is there any chance of buying everything but the pump? Been using the bubbler from compost tea lab. Elaine Ingham seems to say yours produces better tea quality
Sorry for the delay, Tim. I contacted the manufacturer and they said no, they don’t ship the brewer separately from the pump. Note, too, that Dr. Ingham’s comments were referring to the whole package, including the pump. A pump that’s more or less powerful will give different results, and indeed, the KIS people ended up with their brewers based on trial and error of all of the components and a lot of looking through a microscope.
Hi. I want to buy the compost tea brewer but I’m confused about how to apply it. How do you apply yours? In the video it shows you using a hose end sprayer, but then in the description you say that the hose end sprayer is not the best thing to use. I have a 1/2 acre with fruit trees, berries, vegetable boxes and ornamentals. I was thinking of getting a backpack sprayer. Or is it best to to use a watering can? Thank you!
I use a backpack sprayer or at least a standalone sprayer. I’ve listed a couple of my favorites up above on this page. I use a hose-end sprayer for other things, rarely for compost tea. A watering can is great, but not for 1/2 acre 🙂
Hi, I bought the kit and started a brew yesterday. It has been about 17 hours so far and it is not foaming at the top like I see on a lot of videos I have watched. Is that ok? I followed the instructions exactly as written.
Hi Katie, yes, sometimes there’s foam, sometimes not. It depends on the ingredients and it’s no biggie either way. I’ll quote from Dr. Elaine Ingham’s book The Compost Tea Brewing Manual, “The presence of foam on the surface of tea is considered a positive sign, but just means there are free proteins, amino acids or carbohydrates present. This can occur as the result of adding fish hydrolysate, certain organic acids or carbohydrates. If worm compost was used, excessive foam suggests a few earthworms were in the compost and their dead bodies are providing this source of protein/carbohydrate. Excess protein or amino acids should not occur if bacteria are growing well, although dead worms may continue to release proteinaceous materials throughout the brewing cycle. Foam can be suppressed by using organic surfactants, such as yucca or vegetable oil (not olive or canola oil!). Don’t use commercial de- foamers – every single one we have tested kills the organisms in the tea.