Lacto Preparation

This week in the Flog:

  • Making Lactobacillus Serum
  • Photos to go with the recipe!

I finally ran out of lacto serum! It gives me an opportunity to finally publish pictures to go with this recipe. So let’s look at the process from start to finish with pictures.

I didn’t have rice wash handy for the first step. But I did have cheerios. There you go, great carbohydrate source. Not as ideal as a bran cereal or rice wash, but it will do just fine for the purpose of attracting wild microbes. Here is the ‘rice wash vessel’ with at least half air, and open on top. I left the Cheerios in for about 5 minutes, until they started really shedding into the water. Here they are getting soggy:

Lacto Serum Prep - carb wash

Cheerios getting soggy in water, releasing carbohydrates

I strained out the cheerios, and loosely secured some mesh netting over the top so that large critters like cockroaches can’t get in. This is my carbohydrate wash that will sit out for 5-7 days:

Lacto Prep - letting wash sour

The carb wash sits for 6 days to become sour with microbes

Now the vessel sits in a shady area of the garden for 6 days. After 6 days it’s pretty cloudy and you can see ‘threads’ in it – bacterial growths. No separating into layers but that’s ok, it will work fine. I drained off most of this solution since I’ll use the same vessel for the milk, and I need 10 parts milk. So I drained until just about 1/10th the vessel was wash water:

Lacto Serum - wash ready for milk

Wash is strained until it only takes up roughly 1/10th volume of vessel. Now to add the 10 parts milk.

Now we add the milk – just regular old UHT processed milk, nothing special. Although natural cow’s milk would be the absolute best. I put the lid of the jar on top but not clamped down. This creates a seal but if gas builds up it can escape if needed:

Lacto Serum prep - milk added

The milk is added and the jar is capped (not sealed though). The milk sits outside in deep shade for 7 days.

Jar goes back to the shady corner of the garden. Now wait another 7 days. The curd on top starts out pretty thick and gets thinner, while the solution turns very cloudy white. It’s pretty sweet. Here is the jar after 7 days:

Lacto Serum - curds and whey

Lactobacillus cultur – curds floating on top of whey

Now I used the same mesh, in combo with a funnel, to make a strainer to transfer the solution into a plastic jug. Then just pour out the lacto serum:

Lacto Serum - straining off whey

Straining off the Lactic Acid Bacteria (LAB)

Now we have the lacto serum separated out, it needs sugar to stabilize it for storage. I have about 750ml of serum, so it needs either 750ml of molasses or 750gm of sugar. I had nice brown sugar handy, cost <1$ so I like the price vs molasses here. I weighed out around 750gm of brown sugar to be added. Here they are: [caption id="attachment_830" align="aligncenter" width="500"]Lacto Serum - sugar and lacto Sugar and Lactic Acid Bacteria (LAB) ready to be mixed[/caption]

Conveniently I had a 1.5L bottle handy which I added the serum to initially. After adding the sugar, the solution is almost up to the top. Just perfect:

Lacto Serum - lacto serum

The final serum, with sugar added. A few shakes and the sugar is dissolved.

After a few shakes, the sugar dissolves and the solution becomes a bit thicker consistency, with few bubbles. It’s as easy as that. Now I have 1.5L of pure stabilized lacto serum.

How Do I Use Lacto?

  1. Store this pure solution I’ve just made above wherever, in my home office for now.
  2. Get 500ml bottle and add 2tbsp of this pure lacto to that bottle and fill to top with clean, un-chlorinated water
  3. Use this 500ml bottle for all the applications I use lacto for around the house/balcony
    • 2tbsp per meal, after we eat, mixed in half glass of water
    • 1tbsp/L (or less) sprayed everywhere indoors – to kill all those humid-country-tropical-smells that somehow crop up
    • 1tbsp/L to spray plants, foliar feed keep their leaf surface healthy (equivalent to us using after meals)
    • 1tbsp/L when watering compost piles, keep them moist when they dry out
    • 1tsp/L in roach water, dog’s water
    • 2tbsp/L for periodic moistening of Bokashi bran and when adding stuff to bokashi bin
    • 2+tbsp/L drain cleaning – inundate at night after we finish using sinks/toilets
    • 2+tbsp/L grease trap cleaning – in Philippines sinks have bins below them that are grease traps that get super smelly. This kills it
    • 1tbsp/L added to water bucket with organic fertilizer, 12-24hrs before watering plants (usually night before)
  4. When the 500ml bottle runs out, I refill it from the pure lacto serum culture I have standing by

Pretty cool huh? I guess now I need to write a post showing all those applications. The smell killing is a pretty cool one. I should get a video. You can kill smells in 10mins flat. You can have something rotting on your balcony, to the point it makes your eyes water to stand out there. Spray it with a strong lacto mix (5tbsp/L or something). Come out to the balcony 15mins later, and you don’t even know there is some rotting thing there next to you. I speak from personal experience. Hah.

In any case, here is the illustrated lacto serum recipe. Please, share your experiences with lacto, what you’ve used it for and how it’s worked for you. Ideas grow by sharing.

Keep on growing. πŸ™‚

  • peasant

    Hi thanks for posting this info with photos. I am in NZ and was just wondering what the ingredient list is for the cherrios as we do not have the exact same thing here, but may have something similar if I get an idea of the ingredients. The other option is the bran wash or the rice wash I guess. Thanks – loved the article

    • Patrick

      Hey peasant,

      Greetings to NZ! cheerios is just a high-fiber, high-protein, high-carb cereal. You’d be better off with a bran cereal like raisin bran, bran flakes, in NZ you could use muesli (no-fruit muesli) and that would work great. Man, I miss muesli from NZ…That is good stuff. Anyway, the point is just to use a high carb source so any of the carbs will work – any of the brans, rice, etc.


    • Sudheer

      GOOGLE ‘paint thinner in cheerios’. processed foods generally contain preservatives, pesticides, even radio active fungicides, again GOOGLE ‘food irradiation cobalt 60’, apart from the chemicals used in farms.

      • Patrick

        Haha yeah I was wondering about that when I was using the cheerios. But it still seemed to work, got good lacto as the final product..

  • Fil

    Do you need to add sugar if you store in the fridge or is it better to store it at room temperature? We don’t have centrally controlled air conditioning so summers can be pretty brutal.

    • Patrick

      You can add sugar and store it wherever, or store in the fridge and you don’t need to add sugar. πŸ™‚

      • Fil

        Awesome, thanks!

        Do you have any tips for using it in fermented plant extracts?

        • Patrick

          Yeah – use it. It’s awesome. haha but ya, I always add lacto to the fermenting plant extracts – kickstarts the process of fermentation. No real special instructions there, usually I dilute around 1 tbsp/L or so but you can use much less, down to 1tsp/gal and even less than that for large batches. For example if I’m fermenting in a 55gal drum, I’d just add 0.5-1L of lacto.

          • Fil

            Very cool, thanks for the tip!

            Can you clarify step three of “how to use lacto”? Looks like you dilute 2tbsp into a 500ml bottle, then further dilute that when you use it?

          • Patrick

            Yep Fil that’s correct. The first dilution is into the 500ml bottle (roughly 1:20 dilution) then you dilute again depending on your application. So a little lacto goes a long way.

          • Fil

            Awesome, thanks for the clarification! And actually I just completed my first bottle of LAB! Is it supposed to smell like old milk, or have I failed?

          • Patrick

            Nope that’s fine, it will smell like that sometimes, like old milk/cheese a bit. After you add the 1:1 molasses/sugar and then dilute 1:20, it will change and smell more sour/fermented smelling.

      • Magesh.O

        how long will the sugar added serum last long ( active )?
        how long the 2 tbs / 500ml water last long ?

        • Patrick

          the sugar added serum, long time, many months at least.
          after diluting with water, maybe a few weeks outside the fridge. In the fridge, much longer, in the months range I think though I’ve always used them up before then.

          • Have been monitoring the blog for a while now, since a permie friend posted your link about cheerios and milk as culture for LB. I thought he was poking fun at the person with a concern.
            My question is, now having made a couple batches, how to gauge the strength of the Lacto serum and even the diluted as applied drench? Have you or Gil ever done that with a microscope to count LB per field view? (that’s the advice from Elaine Ingham on evaluating compost and compost teas. They hgave a protocol for the count to expect for active compost.)

            And for folks with no micrscope is there a way to k now I don’t have a dead or weak batch?

            Old 99 Farm, Dundas, ON Canada

          • Patrick

            Hey Ian G Old 99 ON Canada, πŸ™‚

            Yep, we’ve looked at batches under the microscope using the soil food web field of view counting method. The 1:20 diluted lacto serum, added at 2 tbsp/gal to plain water, still has around 2000 ug/ml of bacteria which is excellent.

            If you don’t have a microscope there are still ways to see if you have a live batch. The simplest would be to add some lacto to a plastic water bottle, fill with unchlorinated water and a tbsp or two of sugar, and leave that in a kinda warm place. Should get air pressure building up inside within 2 days, as the bacteria digest the sugars. Strength of your lacto batch determines how much pressure you get, and how fast. πŸ™‚

            Hope this helps. Thanks for reading!

  • Fil

    Sorry for the double post, decided to repost this comment with my WordPress account since I notice that is what you are running.

    Do you need to add sugar if you store in the fridge or is it better to store it at room temperature? We don’t have centrally controlled air conditioning so summers can be pretty brutal.

  • Dear Patrick,
    Thanks for the recipe of LAB. Can we use OATS to substitute Rice as, oats , I feel
    is rich in CARB.
    Thanks again

    • Patrick

      Hey Abe,

      Yep for sure you can use oats no problem, they would be a good carb source as you suspected.


  • doyle

    I brew AAC Tea for the garden. Do you have any info on adding LAB to the brew ingredients? Thank You

    • Patrick

      Hi Doyle,

      You can do that no problem, but I don’t think it would add much as the lacto are anaerobic bacteria and wouldn’t do much in a properly aerated compost tea. But you can add BIM and that should be very helpful, I add it in all my compost teas and they are great.


  • Salina

    Dear Patrick, thank you for the recipe. I wonder if can we use yogurt instead of milk in this lacto recipe ? This question came from a friend of mine, so please dont kill me…. πŸ™‚ Thank you…

    • Patrick

      Haha I don’t kill for any kind of question…hmmm well you could I suppose, but you would get less whey think. And it would be more expensive than using milk. Also you would want all natural yogurt, preferably not store bought.

  • Nisha Thomas

    Hi Patrick, I am also making your Lacto solution. I’ve just poured in the milk (organic full cream milk). What I would like to know is how to store the final solution (after brown sugar has been added). Should I store in the fridge or outside in a cupboard or so.

    I am so excited and waiting patiently for the 20th. Thats when the milk solution will curdle and I can pour out the Lacto. Will definetly keep you posted on my progress.

    Best Regards,

  • Nick

    Awesome work with the site! Im new to these methods so its nice to have the data compiled all from the same source.

    “1tbsp/L added to water bucket with organic fertilizer, 12-24hrs before watering plants (usually night before)”

    Im Curious why you would add the LAB in advance to putting it in the soil?


    • Patrick

      Hi Nick,

      Thanks for reading! Sorry for the late reply – you add the lacto the night before, since when you add it, it ‘wakes up’. Assuming your temps aren’t too low that is. The microbes wake up and start multiplying before you add to the soil. It is ideal to combine with organic nutrients since the lacto will consume the organic nutrients and convert them to bio-available forms. Plants don’t use organic nutrients. Microbes have to convert them to their base constituents first. So the ‘night before’ technique does that for you.

  • Mark Trench

    Hi Partick,

    Great site; thanks for all the hard work you must be putting in maintaining it. I have a silly question for you. If I am running out of Lacto solution and would like to make some more, will I need to restart the entire process, starting from creating the rice wash. Or, can I take milk and add a couple of tea spoons of the Lacto solution I have and wait for the microbes to do their magic. I am trying the latter and don’t know if it will work. Hence, thought of asking you.


    • Patrick

      You can just use your current solution, but the rice wash step is for introducing good microbes besides LAB. So you will have less of those in the next batch if you don’t restart.

      Sorry for the late reply, you have probably finished by now haha!

  • Jennie Elsa

    thank you very much for the recipe! just wondering if this is safe to eat like you said – 2tsp after meal mixed with water. what is the benefit of having it as a post meal drink?

    would you let me know?


    • Patrick

      Hi Jennie,

      It is a great probiotic, helps your body digest meals. Try and you’ll see.


  • Big Ray

    Hey Patrick

    It’s wasn’t easy for this old guy to let-go of traditional/chemical ways of gardening! You and Gil have made this natural way of gardening enjoyable, interesting and very important for me, easy to understand the concepts involved. Thank you so much for the information and, for the tremendous effort it must take to maintain this great site.

    Our municipal water-works took a horrible beating from hurricane Katrina back in ’05. A couple of years later a child and a very old guy died from a “brain eating amoeba” that was discovered in our water. Now, the parish adds a ridiculous amount of Chloramine (not chlorine) to our water.


    1. I am starting to make my own biochar. Will a biochar-filled filter (2-feet of 4-inch PVC pipe) act like “activated carbon” and remove chloramine from my water?

    2. The material (Potassium Metabisulfite) used in the wine-making process, also removes/neutralizes chloramines from water. Do you think potassium metabisulfite would be safe to use in my water that I make my Lacto, Bloom, etc… serums with?

    I don’t even like watering my plants with our water. Can chloraminated (sp?) water kill beneficial microbes in my soil?

    • Patrick

      Hey, glad we could help you convert to organic! I’m having tons of fun, and yep the site is pretty busy these days, getting hard for me to keep up with it in fact.

      So to answer your questions.

      1. Not sure if the biochar will do the trick, that’s a tough one.. i would say ‘yes’ but I don’t want you to kill your microbes. there are ways to test for chloramine in the water, though, i would buy a test, then use the filter and test the filtered water.

      2. Not sure the impact of that chemical on plants. Sounds like it would have an effect though, phew.

      3. chloraminated water (lol) would definitely kill the microbes. You should remove if possible..

      Unfortunately chloramine doesn’t evaporate like chlorine (as you know, but for those reading), so removing it sucks. You know where to get great info on chloramine removal though, are aquaculture websites. Like hobby aquarium forums and such. I found some good info there in the past.

      Hope this helps. Sorry I couldn’t be more specific.


  • Zachary

    Hi! I just started my LAB with an oatwash and I have a couple of questions.

    1. In the article you said you didnt get three layers, just signs of microbes. Essentially Im wondering the importance of the siphoning step.

    2. Is it going to take longer if I grow it indoors?

    3. Is the fill level and cover particularly important? Right now I have a 3/4 and 2/3 full containers with a rubberbanded tshirt strip covering them.

    Thanks for this wonderful resource guys! Keep up the good work πŸ˜€


    • Patrick

      Hey Zachary,

      Great questions, glad you’re making the recipes! To answer your questions:

      1. Ideally you would use rice wash, get three layers, and siphon out the middle layer, which is rich with LAB (lactic acid bacteria for those reading) and an assortment of other microbes. That’s the ideal world, but if you don’t get those conditions don’t worry too much about it.

      2. Not necessarily longer indoors. Speed depends on temperature more than anything. Hot temps like body temperature range, are the quickest.

      3. 3/4 and 2/3 full aren’t problems as long as there is some space there. For coverings, t-shirt mesh works. You can even leave them uncovered at the rice wash stage if you don’t have critters you need to keep out.


      • Hi Patrick,

        I’ve just finished the 5-day rice wash. Got the three layers. The top looked good, ie, no black spots.

        It wasn’t yeasty smelling. It didn’t smell bad but it did have a sharpness to it. Is there a smell test? What should it smell like?


        • Patrick

          Hi Mike,

          that sounds perfect! It will probably have a sour type smell.. it went sour as it got infected with microbes. That’s a good thing.. the milk will ensure the lacto take over from here.

          Sorry for the late reply, hope you continued the recipe…


  • Yash

    Hey ! Great to learn this
    Now i wanted to know if i can grow this consotium of lactobacillus in such better way as i have good lab facility here so there wont be chances for pathogens to grow in it.
    You can suggest me how can i prepare this in mass

    • Patrick

      Hey Yash,

      That is awesome. Can you test it also? Can you agar plate them and determine what strains exactly you have? That would be excellent. I’d love to do that with the BIM recipe. Email me and we can discuss further.


  • Yash

    I just wanted to know if i can control smell of died chicks and rotten eggs also

    • Patrick

      Absolutely, it is excellent in controlling those smells. Try it and see.

  • Erik

    Hi. I am a little confused on diluting the lactobacillus for the fish fertilizer application. I understand for all of the other purposes it is diluted 20:1 with water and then used. So with the fish fertilizer do I dilute the lacto 20:1, and then add the 2 tbsp of the diluted lacto per 1 L of my fertilizer solution which is allready 3 parts water? Or am I adding 2 tspn of the undiluted lacto? Thank you.

    • Patrick

      Hey Erik, use the diluted lacto. Yep, add it to the full solution. so mix up your fish, sugar and water. Then add 2tbsp of diluted lacto per L of that solution.

  • Tom M

    Hey Patrick,
    I make cheese on a regular basis and have a generous supply of whey. Since the final product is the culture/bacteria laden whey, could I just use whey in the place of milk?

    Thanks and have a Great Day!


    • Patrick

      Hey Tom,

      I’m not sure actually. I know we use milk because the abundance of lactose suppresses competing bacteria, or rather gives LAB the advantage and makes sure they propagate. I think you need the lactose source which i’m not sure the whey has. If I were you I’d just use the whey like you use the pure lacto serum, its at least very similar. Mix 1:1 with sugar to store, then dilute according to use as per the recipe.


      • Tom M

        Hey Patrick,

        After researching further since leaving the original question, I agree that the LAB serum does indeed need the lactose to isolate the LB.

        Also, I was very skeptical, hell I just couldn’t believe that the diluted serum would actually eliminate nasty odors. I raise chickens and dogs. My dogs are on the ground not in cages so you can imagine the odors we have, especially when we have as much rain as we’ve had.

        So I decided a couple weeks ago to give it a try. I took my pump sprayer went and sprayed all of the dog runs and play yard, , , I could not believe my nose!!! Not only did it work, my wife made comment when she got home that “funny I didn’t smell the dogs when I got home today”

        It works to kill my wifes stinking ash tray odors as well. Thanks!

  • Doug Hurd

    I have been posting links to your site on various threads of a Facebook Group (10,000+ members)I belong to called the Rain Gutter Gardening System. Mostly US, but some worldwide members. Hope this is OK. Just let me know if it’s not OK and I will stop. Love what you do and wanted to let others find you as well. You might check out the RGGS, it’s another great idea.

    • Patrick

      Hey Doug, THANKS! that is excellent you are spreading the word, I greatly appreciate it. Glad you are enjoying the site, keep reading. I’ll check out RGGS, should be interesting.


  • Emma

    Dear Patrick,
    I have a question about using the serum for bokashi. What is the purpose of molasses here? You said if you store it in refrigerator you don’t need molasses, you need molasses if you want to keep it in room temperature. So can I pour some directly into bokashi bin without adding molasses, and store the rest of serum in refrigerator? This way we can save the molasses.
    Thank you!

    • Patrick

      Hey Emma,

      You can use the pure serum for bokashi, but if making bokashi bran it’s best to add sugar also. Sugar is the basic food source of LAB. If you are bokashi composting fruits then no problem. If vegetables, you might want to add sugar. For homemade bokashi bran we add sugar regardless to ensure higher bacteria populations.


  • made my first batch, using wheat, was expecting the layers to be distinct, but it was morel ike a scum on top, some sediment in bottom (of 1L jar), In fact first attempt I used an opaque plastic tub, dumb, couldn’t see what was going on inside.
    So the middle ‘layer’ is supposed to be most of the solution?

    Used raw skim milk 10:1 but did not cover, so not very anaerobic, what effect?

    finally, how do we know we have a potent serum? check pH, do microscope check? smell?

    Ian, Dundas, ON Canada (H Zone 5b)

    • Patrick

      Hey Ian,

      That’s ok if your wheat wash didn’t separate into distinct layers, it should still work fine. It’s also ok you didnt cover the milk. It doesn’t have to be anaerobic but that usually helps keep it free of mold and other contaminants. Yes you can check using all those things. pH should be somewhere below 4, smell should be like sour, or cheese, or maybe a little vinegary but not putrid. In the microscope you should see tons of rod shaped bacteria. Hope that helps.


  • is there a way to verify how strong the lacto culture is, like doing a pH reading or a micrscope count? I have bought lacto motherculture from SCDProbiotics in the past, they say culture is good if pH less than 3.8.

    Dundas ON Canada

    • Patrick

      Hi Ian, quite commonly mine is even lower pH than that. You could do a microscope count, there will be a lot to count depending what field of view size you can get. I encourage you to check those metrics though to be sure you got a good culture going. I’ve had others check the slide count to confirm the 2 tsbp/gal dilution is correct which scoping confirmed. That was their batch though so best to test yours and see how it looks. Let us know how it goes! It’s great to have feedback like that.


  • jb

    can you use lactobacillus in anyway similar to a carbon filter? like on your fish fermenting recipe you have a homemade one, could you put smelly air through some lacto concoction at all

    • Patrick

      Hmmm that would be an interesting experiment, I’ll have to try it. the carbon filter works great in any case..

  • Edgar Melton

    Awsome awsome website you are a master gardener truly I’ve made the BIM growth fert and now I’m trying this lacto I’ve sat it out for 6 days in 90* heat when I made my rice wash I used the boiling water from my BIM after I drained the rice is this going to be ok because when I went to retrieve my rice wash I see little white Cotten balls in the middle layer and I’m not even shor it has 3 layers the top of the wash has nasty white stuff floating on top then 6 in of cloudy Cotten ball infested water with a thick white substance on the bottom now I’m going to be adding my raw milk now ( unpasteurized organic grade) let that go for another 6 days oh and I forgot to say that it dose not smell bad at all as of right now I’m just realy scared I did something wrong if you could let me know it’s all good it would take a load off of me thanks for all th great products

    P.S. That growth fert is the bomb digidy

    Edgar Melton PA USA

    • Patrick

      Hi edgar,

      Thanks for the feedback! Sorry for the late reply, but what you had going there sounds great, it should work no problem. Just strain off the middle layer and add the 10 parts milk, and that should sort everything out.

      Cheers man,

  • omega

    Dear Patric,
    After mixing 1 part of serum with 20 parts of water gas formed & broke the lid.
    this happened in the previous stage also ( I.e, 1 part lacto syrup + 1 part sugar ).
    how to overcome this problem.

    • Patrick

      Hi Omega,

      You’ll need to purchase an airlock, or crack the lid more often to release the pressure. Or, you can leave the lid cracked just a little bit, but this is less ideal since it allows a little air in.

      A few notes: once you add 1:1 sugar, it shouldn’t bubble too much. Also, once you add 20 parts water, ideally you would keep it refrigerated, it will last longer that way.


  • Dear Patrick,

    since the serum can be eaten will you encourage using alkaline water or not necessarily if filtered water will be converted into lower acidity or pH ?


    • Patrick

      Hi Alex,

      I’m not really sure about using alkaline water with lacto – I think it would harm the microbes. You can try and see how it goes, normally I add it to our filtered water (which depending on which brand delivers, can be alkaline I suppose). You can try adding it to alkaline water and see how it works for you.


  • rhuel

    amazing site,its very querry is,can i used condnsed ,evaporated milk instead,we dont have pasteurized milk in about powdered milk and what would be the ratio do i need to dilute powdered milk to water first,what will be the ratio then?..(powdered milk to water?..
    thank you much..very informative website…you’re amazing..

    please email me about my querries..
    thank you

    • Patrick

      Hi Rhuel,

      Thanks for reading! You can use powdered milk no problem, just mix it like it says on the instructions to make liquid milk, then use that in the recipe as your milk source.

      Not sure about sweetened condensed milk, I don’t think so though.


  • Ronnie alido

    Instead of rice wash, can I use natural cane vinegar?

    • Patrick

      Hi Ronnie,

      Actually best to use rice (or other complex carbo) wash. It is a food source which lures microbes in, which you will later harvest. The cane vinegar isn’t as good a food source, it’s already broken down.


  • singaravelu

    hello Patrick and Gill,You are doing an excellent service to those following real organic agriculture.please clarify instead of rice wash why cant we ferment cooked rice, which is known as sondi soru and is being taken as an intoxicant as well a tonic here in Tamil Nadu,India from ancient times.

  • Edi

    Could we use this lacto serum for brackishwater/seawater shrimppond?

Leave a Comment

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>