How To Make Your Own Garden Inoculant For Less Than $1
A garden inoculant is really just anything we use to bring beneficial microbes into our gardens.
These microbes are often deficient for various reasons, but if we can get more of them back in there, they:
- Make nutrients available to plants and even feed them nutrients and water directly
- Protect plants from disease both in the soil and above ground
- Improve the structure of the soil so it has the right amount of air spaces, water spaces, nutrient availability, pH, etc.
Plus there’s a whole list of other services they provide for plants and soil. Pretty cool…
My Favorite Garden Inoculants
High-quality compost is one of the best ways to introduce these beneficial microbes – if you’re lucky enough to have some around.
I’m also a big fan of using a couple of other things:
- Effective Microorganisms (EM) and SCD Probiotics. This is a mix of especially beneficial microbes that do all kinds of good when sprayed on the soil and plant leaves.
- Mycorrhizal Fungi. These are perhaps the most important soil microbes in the world, forming relationships with over 90% of plants.
- Aerated Compost Tea. A liquid produced by bubbling air through a very small amount of quality compost along with microbe foods.
These garden inoculants have had a big impact on my garden.
Making Your Own Microbial Inoculant
But perhaps you’d prefer to make your own inoculant, maybe to save money or to be more sustainable or because you just think it would be cool, man.
What we’re going to do is gather and multiply Lactobacillus bacteria, which are especially beneficial microbes.
I learned this process from Gil Carandang of Herbana Farms in the Philippines.
Personally, I’ve mostly just done it for fun because Lactobacillus also come in EM, which is something I use a lot and know is more useful.
Still, culturing Lactobacillus is great for people who don’t have something like EM.
What You Need
All you need is:
- A small amount of a whole grain such as rice
- Milk for the lactose that will dissuade other microbes from living there while being a perfect environment for the lactic acid bacteria. I prefer organic whole milk, but any kind will do. I used to think cow’s milk was better, but it actually doesn’t matter at all.
Obviously, if you’re a vegan you can’t use milk. I’ve never seen it done with anything else, but I imagine there are other liquid mediums that would encourage Lactobacillus.
Let’s say you’re going to make a pint of garden inoculant, which is a little less than 500mL. That would be 3 Tbsp of grain and 450mL of milk – less than $1 worth of materials.
Rinse the grain in some warm, dechlorinated water.
If your water has chlorine, you can get rid of it by letting it sit out for 24 hours in a sunny spot.
If it has chloramine, you can tie it up by putting pretty much any organic material in there. Vitamin C is often used, but even just a bit of molasses or sugar or lots of things will apparently do it. It happens instantly when you stir it in.
Pour that rinse water into a container, leaving the container 50%-75% empty. This gives us our complex carbohydrates.
Put on a loose lid/paper towel/cheesecloth so that air can still get in, but not fruit flies or whatever else you might have in your place right now.
The grain can be used elsewhere but isn’t needed anymore for this process.
Keep the container at room temperature out of the sun for 2-7 days – the colder the temperature, the longer it takes.
Once you see a thin film on the surface and a sense a bit of a sour smell, strain the liquid into a bigger container and add 10 times as much milk.
This time, it’s better to keep air out of the process, so put a lid on tight.
After the first couple/few days, it’s a good idea to ‘burp’ it by unscrewing the lid and screwing it back on, in case any gases are building up.
In another 2-7 days, you should have some solids floating on top that can go into the soil or compost, and a clear, yellow fluid underneath that contains the beneficial microbes.
Separate this fluid into another container. It will store in the fridge for a year or more.
You can add up to an equal amount of unsulfured molasses or sugar to keep the bacteria fed, which apparently allows it to be stored out of the fridge, but I just keep it in the fridge.
Using This Inoculant
When it’s time to use some, mix it with approximately 1000 parts non-chlorinated water (about 1/2 teaspoon per gallon of water) and spray it as a plant inoculant and soil inoculant.
(When I learned about it this, I was taught to mix it with 20 parts water first, but then that gets mixed with about 60 parts water, so that would mean 1200 parts water total – I just round down to 1000, as this is far from an exact science).
I’ve never seen an application rate, so I just spray my plants until the leaves are dripping.
These lactic acid bacteria will play some role in doing most of the things I mentioned above – making nutrients more available to plants, protecting from predators, etc.
You can also use it as a seed inoculant, soaking seeds overnight with the above dilution.
Feel free to ask questions below.
P.S. Again, I should mention that EM contains Lactobacillus along with other beneficial microbes, and is certainly more effective than using a culture with only Lactobacillus, but still, if you don’t have EM, it’s definitely worthwhile using this one.
Thanks, Phil. You are amazing the way you freely share your knowledge with all of us. Mother Earth is very happy to have you as a mascot. I’m off to soak some rice and begin, even though it snowed yesterday and they’re calling for more snow. My compost bin could use some of this now, as it’s filled to the brim. It’s been a terribly long winter.
Indeed, looking forward to spring…
Thanks for sharing. I want to know if one can use milk power or canned milk and what quantity should we add even though yo mentioned ten times.
Yes, people say that while unpasteurized milk is best, even powdered and canned milk can work okay, but they don’t say how much to use. The exact amount doesn’t seem to matter, though, so just try to approximate regular milk.
Hey, taking 2 cups of whole milk or half/half, add 6 cups water. Worked great.
Can we use milk that’s gone sour?
Phil you do it just for fun?!!I am proud of you for giving credit to Gil for the recipe but there is a little more to it than that. Lacto bacterias are said to be the ,work horse in EM’. Further, they come in many kind. Infect wash at different places and you get many. They are a little more than ‘just for fun’. Also, if you have the luck of knowing about the teaching of Gil, like I do, surely you must know about Dr. Han Kyu Cho, othwhise known as ‘Master cho’. If you do then you know about BIM (beneficial indigenous micro organisms). No need to buy EM Bro. Besides, EM1 are not approved for sale in Canada, that does it for me. Keep up the good work!
Thanks for your input Bob. I’ve heard LAB called the work horse of EM, but it’s the photosynthetic bacteria that are generally considered the most important part. And yet, even more important is how the lactic acid species and yeast and photosynthetic species work together. There are straight lactic acid products on the market, and they can be useful for sure, but they aren’t EM. Of course, we don’t have any peer-reviewed research that compares them. But yes, straight LAB cultures can certainly be helpful, as can BIM. I’m a big fan of both.
Now I’m just speculating here but I have done plenty of fermenting and what you have there for inoculant sounds like whey? I’m now wondering if I can inoculate seeds with diluted whey from yogurt/ home made kefir, live sauerkraut juice or even the liquid that rises to the top of sourdough starter.. though the latter does contain yeasts and apparently alcohol..
Also curious about what plants you spray the leafs of, is this garden veg?
Thanks so much!
Yes, any of those could be helpful, especially those where lactic acid bacteria are dominant – they’re especially good for soil and plant health just as they are for us. I spray on all leaves of all plants!
So can the mother of fermented sauerkraut be used for this process?
I think so. I haven’t seen it done, and I’m not sure what the exact recipe would be, but it makes sense in theory.
Just wanted to remind you that of course indigenous micros are better, but in nature they are not contained and propagates through air and birds.
North america soils were very infertile and it is through Europeans farm animals that soil worms were reintroduced…
I do not believe that this continent had no fertility or worms until the Europeans brought their animals over. Really, where do people come up with this baloney?
The bison ate ice cubes before Contact.
Earthworms existed in North America wherever the Ice Age glaciers did not advance. In the northernmost reaches of the US, earthworms were indeed reintroduced (non-native species) when European settlement occurred post-17th century.
And yes, there definitely was extant fertile soil in North America, Nadia. It’s called the prairies of the central US and southcentral Canada. And most of the hardwood forests (no pines) in the east-central parts of the continent had ample organic and microbial situations prior to colonization and deforestation.
Can I use whole organic yogurt?
Certainly, although I don’t know how much.
Hi Phil I’m starting a garden from scratch. The whole thing was grass. I bought the calcium carb and different things from you but they are mostly liquid. When I am done getting all the grass out, im buying compost (only this time) to mix in and adding the calcium but after that, should I spray the liquids on top of the soil? Of course when I plant I will add the mychor. Fungi to the roots of my plants but wasn’t sure about the liquids. Thanks
Hi Melissa, yes, it’s nice to do your first spray on top of the soil while you’re doing this or at some point within a few weeks before planting. It just helps get the soil into better shape before planting.
Melissa, your garden sounds interesting.
Just yesterday I was listening to a youtube by Paul Gautschi, “Back to Eden Gardening.” You would enjoy listening to his teories, I think.
Grass, Clover and related are nitrogen-fixing. You do not have to rout oute grass roots, using Gautschi’s method. He applies 4-6″ wood chips right on the grass, which utilizes the green grass for nitrogen to break down the wood chips by contact; and at the same time it kills the grass on the spot. No tilling.
To plant your garden, make deep rows down to the soil level, plant your seeds or plants in the soil. When the seeds come up, pull the chips together as a mulch. Maintain your chip application by adding on top. Do not cultivate the soil. It will become soft, hold moisture, and be fed by the decomposition of the chips. All the activity happens at the point of contact between soil, grass and chips.
When he harvests his potatoes, he chooses his best and replants all at the same time. He saves all of his own seeds. As he continues gardening this way, the produce gets better and better. He feeds his abundant produce to his chickens and harvests their poop to fertilize the garden and keep the process cycling. His dog keeps out the deer. They also eat the produce. A Vet. M.D. checked his dog and found him to be in perfect health.
Initially, it seems the Inoculation tricks learned from this site may be helpful for stimulating plant growth, fixing Nitrogen, protecting from diseases. But after you get going your soil will become better and better, and with much less effort. That is what I want to do.
I was wondering if you could make a spray with water and a lactobacillius mixture from a probiotic capsule. Not that I don’t enjoy a fermentation challenge. It just seems like a lot of material for what is used individually.
Yes, you absolutely could. As for how much, I must say I have no idea, but certainly worth a try.
I may be completely on the wrong track here, but can you use this microbial inoculant to make your own bokashi mix? Will it keep ok mixed in with the dry materials?
Yes, you can use this for bokashi. It would be nice to mix in a bit of compost to have a more diverse set of microbes, but it’s possible the lactobacillus would do an okay job on its own. I’d be interested to try it actually.
Oh great! Thanks Phil.. I’ve still got a couple of bags of bokashi mix left, but was just starting to think about how I could easily make my own without setting up the full compost tea setup just yet.. Will give it a go when we get close to running out 🙂
Thanks for sharing this. If I chose to store the inoculant outside then how long or often should I feed it with molasses ? Also, how long will it stay ok ?
I would only feed it once with molasses, and I’m not sure how long it will stay okay. I suppose it depends on the temperature. When it gets hot out, it will go bad more quickly, maybe even within a few weeks. When it starts to smell bad, it’s time to dump it.
I am assuming, Phil, that you meant to say dump it into your compost bin/pile when it smells bad. Never throw in the garbage a nutrient dense decomposing substance that can be composted. It might be best if it is in a closed compost system. One that big critters can’t get into. Thanks again for the recipe. Plan on using it to inoculate my peas and beans this year. Those small packages at the garden center can be pretty pricey. Thanks again!!
How is this lactobacillus treatment you outline above different from diluting milk 1 part to 10 (total) parts and spraying that on? Is this just a more cost effective method 🙂 ? Thanks for your contributions. Bob the anti-Slug had a good comment about Canadian regulations; A few things are available up here like Harpin and EM.
I’m not sure I understand your question? Milk is not a fermentation, so doesn’t contain much in the way of lactobacillus. Yogurt, on the other hand, would probably bring some benefits. Not sure of application rate, but I’d just mix it in water and spray the whole garden.
I use the milk and water mix to deter/eradicate fungus on the leaves of a lot of my plants. I live in the tropics so fungus is a common problem here. I love the way you freely share your garden knowledge Phil – thanks so much for all you do for the wider gardening community. This sounds like a great recipe.
Really, your just using the fermented whey, right? I make milk kefir daily, gotta try this. What about left over (excess) kefir grains? That is a scoby (symbiotic colony of bacteria and yeast). It’s useful for bowel flora, gotta be good for soil. Which seeds do you soak in this? Think I’m only used to soaking beans. Thank you very much for your time and expertise! And you’re ebook if wonderful, it officially turned all of my gardening “knowledge” upside-down. I’m so excited to give biological gardening a go. I’m sending out a soil test asap.
Yes, all of those fermentations we make for ourselves probably have some benefit in the garden – they’re often based on lactic acid bacteria. I soak all seeds in this kind of inoculant – just at the very diluted ratios though. Thanks for the compliment!
Hi Phil and Neil, I also brew water and milk Kefir. How exactly have you used it and have you seen the results???
Thanks for sharing….I live in El Salvador and the weather here is tropical but have learned soooo much!!!
Hi Norma, I’ve been all about making kombucha for the last 3 years. I don’t know how much of a difference it makes for my health, but it tastes great. I haven’t used kombucha in the garden.
I understand that beans and peas require particular types of inocukants. Wi this work for them?
No. This inoculant can be used with beans and peas, but it’s not the one you’re referring to.
Thank you for helping the amateur gardener. You website is most helpful! What do you suggest to use for tomatoes?
I don’t do anything different – just use all of my usual inoculants and fertilizers.
hi phil, you seem to be a nice person for always sharing your knowledge with eveyone. i live in india and we use a fantastic fertilzer, totallly organic called the panchgavya. u should look it up, it is made up of 5 cow products. cow dung, cow urine, cows milk, curd, and molasses . just mix it for a period of 15 days and then strain and spray on yr plants or just feed it to your plants after diluting it 2 parts to a 100. just fantastic. let me know if u make it.
In North America, most of our cow dung contains antibiotics and hormones, so I’m not in the habit of using it much. And I don’t drink milk, so I don’t have it around usually. But if I had my own cows, I would definitely experiment with this.
How often do you use this? Can you use too much?
It is possible to use too much, although I’m not sure how much that would be. I do it once/month. It could be done daily if a lot less was used.
Can what you made be put into a pond filter to produce benificial bacteria to help keep the pond clean and balanced ?
It could help a little. I know EM and SCD Probiotics definitely help clean pond water.
Phil, is there any way to measure this to use on a hose end sprayer. I have a large yard and mixing by the gallon would take forever. By the way, as everyone else has said, your knowledge and sharing is amazing! Thank you.
Ya, if you mix the inoculant with 3 parts water and put that mixture into the hose-end sprayer (e.g. 1/2 cup of inoculant with 1 1/2 cups of water), then set your sprayer to 1 Tbsp per gallon of water, you’ll have a 1:1000 ratio.
I learned a lot from your post about planning your landscape. Thank you. I wonder if you have any advice for me as I am renting this home with permission to garden. It is poor soil and has not been cared for in about 8 years. There are fruit trees (apple, plum and pear) that are in desperate need of pruning and are infected by bugs. There are overgrown ivy and blackberry canes at the back of the property. I just would like your ideas on what comes first … what next. At the moment I am a bit overwhelmed.
Pruning the ivy and blackberry is definitely the easier place to start, as pruning fruit trees requires more knowledge. That said, if the blackberries are going to fruit this summer, you may want to wait until after that to prune.As for the fruit trees, they’re usually pruned in late winter/early spring. Summer pruning is okay, but fall pruning isn’t done as much because it can increase the risk of winter damage. If you’re new to pruning, you may want to read up on it this summer and perhaps do a small amount for practice, then more in the spring. Either that or hire an arborist, because pruning does take some knowledge. Note that pruning doesn’t generally get rid of insect pests – it’s done to increase fruit production and quality.As for the soil, you’ll find lots of info on this site about how to improve that – be sure to sign up for my free ebook download if you haven’t already 🙂
My father-in-law lives in Utah in the US and he has a huge orchard. His method of controlling bugs is brilliant. He has driven a spike into each tree trunk and takes a generator on a cart to each tree hooking it up to the spike. He starts it up and applies electricity for 15 seconds or so.
Bugs fried and gone… fruit bug free and lovely.
I used the rinse water from some whole grain brown rice noodles. Problem is that the noodles were cooked in that water not just rinsed. I’ve already made the innoculant but am not sure if it will work. It keep congealing even after I put it in the fridge.
Can you eat that weird cheesy part afterwards? Or use it for something? Thanks
You can put it in the garden.
This will not work. Reason is there are many hundreds of species of bacteria out of which only one works with peas, legumes, etc., It will not hurt you to try, but it is a waste of time.
This article is not about the legume-specific inoculants you’re referring to Lumakar – it’s about growing species that are beneficial for all plants.
Can you give references?. You can also take virgin soil from forest or undisturbed area and add it to culture.
Not sure it’s a good idea to advise people to take virgin forest soil. Can you imagine hoards of gardeners digging up forests? In addition to ruining the virgin soil structure and harming the plant, animals and microbial life, humans track in invasive bacteria which can effectively destroy an entire forest. We care for nature, correct? So why would we destroy forests just to benefit our gardens? Seems awfully selfish. Those forests are in enough trouble already. Let them be and use some of Phil’s suggestions here.
Buy inoculant from INTX or BeckerUnderwood or others. They got specific bacteria in a packet you can use.
Couldn’t find INTX but Becker Underwood has been purchased by Germany’s BASF and all of the listings seem to deal with corporate transactions and not nurturing crops! Is this another example of a large (probably polluting) company buying up a smaller company with organic technologies in order to bury them? The sale was in 2012.
Thank you for sharing. Can I use whipping cream because I have no milk in my fridge. Also, can I spray on all my plants. Thank you.
I’m not sure about whipping cream, Sophie. It’s certainly worth a try. It often has sugar in it, but that’s okay. I would try it on one plant first, but yes, I imagine it’s okay for all plants.
Thank you for your answer. I have started one batch using 2% milk ( I went and bought a jar just for this purpose) Currently, it is sitting on the shelf in my shed in the back yard. I have another question for you: You mentioned before that if we mix the inoculant with 3 parts of water and put the mixture into the hose end sprayer ie. a/2 cup of inoculant with 11/2 c water, then set the sprayer to 1 tablespoon per gallon of water we will have 1:1000 ratio. My question is: Wouldn’t the water come out be tap water which is chlorinated? I live in Vanouver area and it is really not easy to save rain water during Summer because it can go without raining for a few months. I am hoping that I can use tap water to spray because I have a huge garden with a lot of fruit trees and vegetables. I fermented my fruits to use as fertilizer and I hope that I can mix this with my fertilizer for my garden. Since my fertilizer is acid base should I dilute the ratio even more. Currently, for every 2 cups of tap water, I add in 1 teaspoon of fertilizer. Thank you very much.
Hi Sophie, chlorine (or chloramine) in the water isn’t ideal, but it’s something many of us have to live with, and it’s not the end of the world. Some of the microbes won’t love it, but many will be okay. As for the pH of your fertilizer, a little bit acid is actually a good thing. At 1 teaspoon for 2 cups of water, I expect you probably don’t have to worry about that.
Hi Phil, Thank you very much for your advice. I have one more question to ask you.
My husband dumped whole bunch of apples that were infested with maggots into the compost pile and I do not know how to deal with it. Do you have any Suggestion? Thank you.
I just wouldn’t use that compost on your apple trees (and whichever other plants those particular insects like to eat, if any). But on than than, the maggots/flies should be kept in check fairly quickly once spread into the garden, provided you have a reasonably diverse ecosystem.
Hi Phil, Thanks again for your suggestion. Currently, I just use molasses mixed with apple cider to try and catch codling moths. I sprayed dormant oil mixed with surphur on all tree trunks. I hope it helps.
Hi Phil, I have a question to ask you: whenever peach trees contacted rain, they will have leaf curl which is some kind of fungus disease. Can l spray lalactobacillus-serum on the leaves to prevent leaf Curls?
Sorry I missed this earlier, Sophie. Yes, you certainly can spray the leaves with the serum. It may help.
Thanks Phil. I am wondering if hydroponic nutrient solution (like Botanicare) would work as an inoculate for peas growing in soil?
It may have some use as a fertilizer, but it’s not an inoculant. For that you need an actual pea inoculant.
Nicely done, and thank you for helping others to improve their own smaller parts of our world, but there’s a few things we should all think about:
I had been culturing various aerobic bacteria, until I realized that identifying every specific strain wasn’t feasible (now cycling continually, and sterilizing occasionally). Relying upon one’s luck isn’t a good idea, since the WRONG bacteria holds the potential to make our own luck so VERY bad.
Inoculants are not just “any good ol’ bacteria will do,” even though they’re beneficial, as often the species required are very specific to the plant (e.g. your best scenario would cause my crimson clover to not fix Nitrogen well, leaving potentially an extra hundred pounds or so per acre in the winds, as they carried away as many pounds of our soil).
Now, just for fun? Folks that don’t wish to eat the products from animals can still use them, just as those of us that choose to avoid eating pork could raise pigs. There are actually eggs being marketed as coming from vegetarian chickens. <~ seriously.
I hope you keep experimenting, and sharing your results with others — it's what we all should do, since the better solutions are most often found by us common folks. And, our world sure needs 'em.
Can’t I just mix some active yogurt in my compost to healthy bacteria?? Lol sounds dumb but ya never know.
Yes, you can. This lesson was more about making a very affordable liquid inoculant to spray on plant leaves.
I cannot find a homemade pea inoculant. I see you said above that this not a legume-specific inoculant. Do you know of one or can you direct me to a (free) on-line source for one?
Unfortunately, there’s nothing I know of.
Hi, C.J., and thanks again to Phil for maintaining a good resource for all.
I’ve propagated mycorrhizae for use here, and rhizobia for experimentation (which costs far more than purchasing inoculants as needed), but us regular folks aren’t allowed to transport bacteria.
This PDF, provided by the USDA, provides the inoculant code specific to each variety of plant… https://www.nrcs.usda.gov/Internet/FSE_PLANTMATERIALS/publications/etpmctn12525.pdf … and gives good instruction on innoculating seed. If your variety isn’t listed? Holler back, and I’ll try ‘n play ‘matchmaker’ for your seed.
I have tons of water kefir grains. Can I mix those with filtered water, some molasses or sugar, lt sit for a few days then apply the whole thing to a lwan in need of care?
Not sure if that will work, but there should be some way of using the grains.
I will try it and let you know if it works. I found some nice black dirt under my deck, I will throw some of that in too, and see what happens.
Hi Phil.i am planting okra and its getting into winter soon. I stay in tropical island. It does not sbow here. Will winter affect my okra plants. Im using mulch to protect the plants. Is that enough or do i have to put something else in my plants.
It depends how cold it gets there but okra doesn’t mind some cold so it sounds like you’ll be okay. Just a guess, though – I’ve never grown okra in the tropics 🙂
After diluting in water what is the shelf life? How long will the bacteria survive once diluted?
I’m not sure how long they’ll live but after a couple of days the usefulness will drop off quite a bit.
I’m new to this and have lots of questions.
1. Will this work for soaking a few pea seeds as my seed packet urges, or do I need an inoculant especially for legumes? (Small yard so I guess I don’t need a lot.)
2. My city does the chloramine thing. Can you suggest an amount of sugar and of water please?
3. Again, how much rice? And when you say “rinse” the rice, does that really mean to just pass the waiter over the rice or to soak the rice in the water for a while?
1. You need the legume inoculant. It’s not mandatory but usually helps a lot.
2. I haven’t found good data on this. For one thing, it depends on how much chloramine your water has, and also depends on the type of sugar. I’m guessing 1 Tbsp of sugar per gallon of water but that’s just a guess.
3. If I want 1 cup of rice wash, I’ll have 1 cup of water and about 1/2 cup of rice. As for the rinsing, I swish it around for maybe 20 seconds. Here’s a more thorough article: https://www.unconventionalfarmsupply.com/lactobacillus-serum
Great page, really enjoyed it. Just wondering how this innoculant would go on Eucalyptus seeds pre-sowing. Lots of Eucalypts have such poor germination rates so I’m looking to do all I can to get them to germinate.
Thanks for any thoughts you may have!
Hmm, I hadn’t heard that they have germination issues. I suppose it depends on when the germination is a problem. If the radicle can’t even break out of the seed coat, I doubt any inoculant would help much. But if the germination problems come later, from disease or biology/chemistry deficiencies, it’s possible the inoculant could help.
Hello. I made this several weeks ago and am excited to use it! Thank you for sharing!! I used sugar to “feed” it instead of molasses which seemed to be ok. I have had it out of the fridge for a week or so and it is starting to get cloudy bits in it. Is it still usable, is this normal?
Yes, no problem at all, Terra. Go for it!
Will organic yoghurt or kefir (fermented milk) work instead of the milk?
Can this inoculant be used on house plants?