ProBio Maru and Danu - My findings

Wires_Guy_wires

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After some shipping issues, I finally received my Liquid ProBio Maru and Danu in the mail at the end of spring. Most plants were pushing, but not a whole lot at that point. So I think that I've missed the ideal window, but only by a couple weeks.
The stuff smells like school and work, so yeah, those are live cultures for sure.

I did a couple comparison tests because I want to know whether or not some of the claims hold any ground in a practical sense. Harry Harrington in particular, has made wild claims about the stuff; it would be able to cure juniper rust completely, it would be able to stop mildew and shorten internodes on hawthorns.
I wanted to do a full seedling experiment and a side-by-side comparison of treated versus untreated, but that was impossible due to circumstances. So I just treated all my seedlings and compared the results with last years seedlings outcome.
Here's my findings after finishing the bottles, spraying in intervals of 2-4 weeks at the recommended dilutions:

Mildew
Quercus roburMildew still present after 5 treatments, NOT present in untreated group
Portuguese LaurelMildew still present after 5 treatments
Various other garden plantsMildew still present after random treatments

Unknown type of "root rot" in indoor plants
Completely cured

Unknown type of root rot / Damp(en)ing off of outdoor plants
Maple seedlings (trident)All dead / No difference
Pine seedlings (rigida, sylvestris)No difference
Hawthorn (2021 yamadori, small spots on foliage in spring)Dead / No difference
Rooted juniper cuttings with some moisture issues (kishu, itoigawa)Dead / No difference

Shortening of internodes
Pines (scots, mugo, JRP, JBP, Banksiana)No difference
Junipers (chinensis, shimpaku, rigida, Media/Pfitzer, and others)No difference
Prunus sp.No difference
HawthornNo difference
Cotinus coggygriaInternodes six times as long as last year, likely shaded condition confound. Worth mentioning because internal effects of the plant seem to be uninhibited. As in: no obvious auxin dampening.

Growth looks better and plants look more vivid, with fewer overall issues
Strawberries - although fruits still rot as fast as normal, plants look healthier and are more resilient
Tomatoes
Citrus (mandarin, citron)
Allium sp.

Plants tested but no sign of any growth difference, and/or no stop of issue progression
Olive (Olea europeana)
Thyme
Citrus (Citrus australasica)
Maple (cork bark japanese maple)
Spruce (Picea abies)
Cannabis - Still waiting on botrytis results though, bud rot usually occurs in fall here
Juniperus Osteospermum
Prunus sp. (various types of cherries and plums)
Juniperus communis
Various other annual garden plants
Grapes
Various outdoor succulents
Juniperus sabina var. rastrera
Alnus nigra
Everything else in the yard that got sprayed


My conclusion: Still waiting on the new spring for a juniper rust comparison between treated and untreated groups. In indoor potted plants, this stuff is magic. Simple as that. It solved an issue I've been dealing with for about 8 years; random root death due to over and underwatering. The strawberries look healthier than ever and seem to be waaay more resistant to drought. Also there is less death in the strawberries overall.
That being said, I've lost a hawthorn and various other plants due to bacterial root issues this year. Untreated junipers actually performed better at bouncing back. The mixture seems to be effective to some pathogens, but not a wide array. My arakawa maple has spots all over, and my european oaks still get the millie dewy. My portuguese laurels haven't improved, so it's back to antibiotics for them.
All in all, stick to the claims on the probio website - and take those with a grain of salt - and don't get carried away by claims that bonsai professionals make because simply put.. Very few of them know about microbiology.

My opinion: Maru and Danu can be a great tool to have for some moderate issues and in indoor potted plants they both have real promising results. The smell though is comparable to coleslaw and morning urine mixed in a bowl. That's something not everyone can stand, it lasts for about a day though.
Is Maru a one-cure-for-everything? Absolutely not. Does it prevent mildew or other fungal issues? No. Does it stop bacterial problems in outdoor plants? Also no.
Especially the growth pattern effects of Danu are lacking; I see no more backbudding, no tinier internodes, no smaller foliage. Also no increase in growth compared to last year. Which makes me think Danu isn't doing what it should in my backyard.

Would I buy it again?
The Maru, yes
. Because my indoor plants keep me sane in winter and I want them to be happy. Also, the strawberries seem to like it. But then again, my indoor plants are ornamental and antibiotics are cheap. A single flask of Maru costs me about four times as much and expires relatively fast. I'm also not comfortable with keeping live microbial cultures in my food fridge.
The Danu? No. I'm not convinced. A side-to-side comparison showed no differences in a whole range of plants. I also find it remarkable that it's called a growth promotor and the description is about disease resistance.
 
Thanks for doing some comparison.
 
Update on the fungi in the botrytis family, grey rot or whatever you want to call it:
Both the strawberries (fruits) and the cannabis (flowers) have it. To the extent that I don't believe these products to have an effect against it.
I'm willing to give in and say that the strawberry fruits are difficult to protect as they grow from flowers and they contain a whole lot of sugars. But cannabis flowers all originate from the same meristematic tissue as the foliage and branches do, so there doesn't seem to be a "protective film" of commensal bacteria or the so-called siderophore activity against botrytis.


Even though they were extensively treated multiple (>5) times since the seedling stage. Both soil and plants.

The products don't seem to have lasting effects that protect plants over the seasons.
I was truly hoping otherwise!
 
I have a similar experience trying to save a juniper from "tip blight".

As long as you treat, progression slows down.

Once you stop treatment , the tree dies.

The products don't seem to have lasting effects that protect plants over the seasons.
 
After some shipping issues, I finally received my Liquid ProBio Maru and Danu in the mail at the end of spring. Most plants were pushing, but not a whole lot at that point. So I think that I've missed the ideal window, but only by a couple weeks.
The stuff smells like school and work, so yeah, those are live cultures for sure.

I did a couple comparison tests because I want to know whether or not some of the claims hold any ground in a practical sense. Harry Harrington in particular, has made wild claims about the stuff; it would be able to cure juniper rust completely, it would be able to stop mildew and shorten internodes on hawthorns.
I wanted to do a full seedling experiment and a side-by-side comparison of treated versus untreated, but that was impossible due to circumstances. So I just treated all my seedlings and compared the results with last years seedlings outcome.
Here's my findings after finishing the bottles, spraying in intervals of 2-4 weeks at the recommended dilutions:

Mildew
Quercus roburMildew still present after 5 treatments, NOT present in untreated group
Portuguese LaurelMildew still present after 5 treatments
Various other garden plantsMildew still present after random treatments

Unknown type of "root rot" in indoor plants
Completely cured

Unknown type of root rot / Damp(en)ing off of outdoor plants
Maple seedlings (trident)All dead / No difference
Pine seedlings (rigida, sylvestris)No difference
Hawthorn (2021 yamadori, small spots on foliage in spring)Dead / No difference
Rooted juniper cuttings with some moisture issues (kishu, itoigawa)Dead / No difference

Shortening of internodes
Pines (scots, mugo, JRP, JBP, Banksiana)No difference
Junipers (chinensis, shimpaku, rigida, Media/Pfitzer, and others)No difference
Prunus sp.No difference
HawthornNo difference
Cotinus coggygriaInternodes six times as long as last year, likely shaded condition confound. Worth mentioning because internal effects of the plant seem to be uninhibited. As in: no obvious auxin dampening.

Growth looks better and plants look more vivid, with fewer overall issues
Strawberries - although fruits still rot as fast as normal, plants look healthier and are more resilient
Tomatoes
Citrus (mandarin, citron)
Allium sp.

Plants tested but no sign of any growth difference, and/or no stop of issue progression
Olive (Olea europeana)
Thyme
Citrus (Citrus australasica)
Maple (cork bark japanese maple)
Spruce (Picea abies)
Cannabis - Still waiting on botrytis results though, bud rot usually occurs in fall here
Juniperus Osteospermum
Prunus sp. (various types of cherries and plums)
Juniperus communis
Various other annual garden plants
Grapes
Various outdoor succulents
Juniperus sabina var. rastrera
Alnus nigra
Everything else in the yard that got sprayed


My conclusion: Still waiting on the new spring for a juniper rust comparison between treated and untreated groups. In indoor potted plants, this stuff is magic. Simple as that. It solved an issue I've been dealing with for about 8 years; random root death due to over and underwatering. The strawberries look healthier than ever and seem to be waaay more resistant to drought. Also there is less death in the strawberries overall.
That being said, I've lost a hawthorn and various other plants due to bacterial root issues this year. Untreated junipers actually performed better at bouncing back. The mixture seems to be effective to some pathogens, but not a wide array. My arakawa maple has spots all over, and my european oaks still get the millie dewy. My portuguese laurels haven't improved, so it's back to antibiotics for them.
All in all, stick to the claims on the probio website - and take those with a grain of salt - and don't get carried away by claims that bonsai professionals make because simply put.. Very few of them know about microbiology.

My opinion: Maru and Danu can be a great tool to have for some moderate issues and in indoor potted plants they both have real promising results. The smell though is comparable to coleslaw and morning urine mixed in a bowl. That's something not everyone can stand, it lasts for about a day though.
Is Maru a one-cure-for-everything? Absolutely not. Does it prevent mildew or other fungal issues? No. Does it stop bacterial problems in outdoor plants? Also no.
Especially the growth pattern effects of Danu are lacking; I see no more backbudding, no tinier internodes, no smaller foliage. Also no increase in growth compared to last year. Which makes me think Danu isn't doing what it should in my backyard.

Would I buy it again?
The Maru, yes
. Because my indoor plants keep me sane in winter and I want them to be happy. Also, the strawberries seem to like it. But then again, my indoor plants are ornamental and antibiotics are cheap. A single flask of Maru costs me about four times as much and expires relatively fast. I'm also not comfortable with keeping live microbial cultures in my food fridge.
The Danu? No. I'm not convinced. A side-to-side comparison showed no differences in a whole range of plants. I also find it remarkable that it's called a growth promotor and the description is about disease resistance.
what is your water source when you did these tests I just watched the Peter Warren interview and he says people that don't have great results are due to the water used, he suggests using rainwater or off gassed 48 hour tap water, he says the chlorine will kill the beneficial bacteria. In my comparison I will be using it on some maples in pots using filtered water, using water collected from the nearby davidson river which has a fishery on it(had amazing fall color one year using that water), using water in my spring and then plants in the ground that I am field growing.
 
Well.. living lake front. I didn't treat for fungal in my pots. Yet it was prominent in my landscape. The only difference? I used Danu and BioChar.

That was my findings... it was the first year I never treated with fungal treatments... Second year of using products.

Speaking of 2024 growing year.
 
what is your water source when you did these tests I just watched the Peter Warren interview and he says people that don't have great results are due to the water used, he suggests using rainwater or off gassed 48 hour tap water, he says the chlorine will kill the beneficial bacteria. In my comparison I will be using it on some maples in pots using filtered water, using water collected from the nearby davidson river which has a fishery on it(had amazing fall color one year using that water), using water in my spring and then plants in the ground that I am field growing.
Hmmmmm interesting.
 
what is your water source when you did these tests I just watched the Peter Warren interview and he says people that don't have great results are due to the water used, he suggests using rainwater or off gassed 48 hour tap water, he says the chlorine will kill the beneficial bacteria.
I test it annually and my source is the tap that it comes from. I believe my test kits are up to par as we use them in the lab too.


Not to forget these bacteria are spore forming, so even if my water was bad, in the six months or so my plants only get rain water those spores should have germinated and I should have gotten the positive effects. That's how bacterial spores work.
I have yet to see any publications by Karen about these products that follow a scientific approach. When a company is commercial, and making these kind of claims, I want to see it backed up by at least a comparative study. They can even fake the data, I couldn't care less, the fact that someone with a doctors title and three publications to her name, isn't doing comparative science sounds fishy to me. I did a poor test, absolutely! But I'm not putting bread on the shelves with comparative bacterial studies anymore. That was my work in the past.
I'm in touch with some people in the plant industry, from my previous work and some researchers at universities and they are all unfamiliar with these ground breaking bacterial cultures that should change the world. Most of the beneficial effects can also be achieved with bacterial lysates or sodium free marmite.
Bonsai artists who have studied plants their whole lives, and get told stuff, tend to make wild claims but they also tend to forget to rule out any confounds.
See Ryan Neil and his compost tea accidents.
 
Shoot...I dumped it all over me! BioGold juice...as I make a tea. I was watering over my head... half my head...down my shirt and into my waste band of my pants. I was lovely.

I mentioned it on Instagram...with a photo. I've since removed most photos of myself there though. So it's in archives.
 
where do i see that?
I think he said it was on his mirai pages somewhere. The podcast has a couple parts about it; some organic farmers convinced him to start composting - bokashi was a craze in the early 2010's and these people adopted their own version.
The tea got too hot, it contained the wrong bacteria (degraders only; which can turn pathogenic) and the application turned out horrible.
 
Shoot...I dumped it all over me! BioGold juice...as I make a tea. I was watering over my head... half my head...down my shirt and into my waste band of my pants. I was lovely.

I mentioned it on Instagram...with a photo. I've since removed most photos of myself there though. So it's in archives.
That sounds very unpleasant! Luckily it wasn't fresh manure. Although urea is a great skin moisturizer.
While we're on the topic: akadama dust makes very, very bad face mask clay!
 
That sounds very unpleasant! Luckily it wasn't fresh manure. Although urea is a great skin moisturizer.
While we're on the topic: akadama dust makes very, very bad face mask clay!
After the initial gasp... I laughed myself silly. finished fertilizing...then grabbed a shower. I WAS RIPE!
 
Any clue on if Danu is ok to get on your hands? After watching the peter warren videos he gets it all over his skin and doesn't bat an eye. Also has anyone used the dried danu while making airlayers?
 
Any clue on if Danu is ok to get on your hands?
this seems to be just a naturally occuring bacterial culture, so if you are find with getting your hands dirty when working compost and soil, this product should not bother you. Who knows; a side-effect might be better skin. It has so many magical properties.
 
Any clue on if Danu is ok to get on your hands?
It is safe to handle plants treated with it.
Live bacterial cultures are highly concentrated and can cause rashes, and there's enough on you to still be there after a good washing. So wash up well, clean the fingernails and maybe use some 70% alcohol just to be sure.
Your skin is about the best barrier there is for keeping things out, and these bacteria are not known as human pathogenic.
But I would still avoid touching food that is being stored afterwards, for that day. Eating it right away is fine, your stomach will kill whatever is on there. In stored food, they can freely multiply and you wouldn't want that. It's not that it will kill you but it might upset the intestines.
 
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