Compost tea thoughts

I was recently talking with a family member who is a horticulturist (doesn’t practice bonsai). he asked me if i used compost tea, me just recently starting bonsai and really being a beginner in the whole horticulture aspect of things all together didn’t know what it was. to shorten the story a little he told me it can greatly benefit the root system adding helpful bacteria and what not. I’m curious if anyone else uses this as a type of fertilizer (seems to have huge benefits) and the successes or downfalls this might bring?

i know roots are super important so to me it seems useful but i am new to bonsai and things react different in our smaller pots and soil compounds

Mirai did an experiment with compost tea and the short answer is that it didn’t work for Mirai. There are three podcasts (with Ian Hunter) on the experiment if you want to learn more.

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Don’t do it! Ask Ryan :grinning:

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oh wow that bad lol well glad I asked questions about it first lol

ill have to listen to thoughs glad i asked some questions first lol
thanks for the info

I personally think it’s a topic worth exploring a little more, but there is pretty strong evidence that the bonsai container is different enough that it’s not a quite the same as other types of container cultivation.

In the UK/Ireland we are using a new product called Danu from ProBio Carbon in Ireland. It takes the bacteria selection a lot further than compost tea and has been selected by a very experienced soil scientist with some guidance from a qualified bonsai professional and hobbyists. It is a live culture with a very short shelf life in low temperatures though a dried version has just been established. which is easier to ship. Results so far are very encouraging though still early days.


Explanation on Danu is in this video from Peter: Soil health for bonsai - Live Stream with Peter Warren - YouTube

Yeah I think Ryan mentioned getting some of the dried stuff shipped to him from Peter in their podcast. Very interested to see how it works for him.

Maybe it’s just me… the world is getting smaller…
Anybody know why the American Chestnut is almost extinct? They used to COVER the eastern seaboard to the great plains. Indigenous people subsisted on them for thousands of years.
A fungus was accidently imported from Asia in the early 1900s. Quickly spread and killed (almost) every tree…
I would be carefully using any imported LIVE innoculent… Wild strains always have pathogenic potential… I get infections from working with the soil all the time. Bacterial AND fungal (nail fungus anyone?).
Anybody else ever open a shipment of bananas and find a live tarantula… Funny how life moves around.
I think that is what happened with Ryan’s compost tea debacle. Pathogenic bacteria , fungus, and viruses grew WITH the good bacteria in the compost / tea. Plant pathogens are usually anarobic (Don’t like oxygen). Airating the compost and tea is important… When it’s done well, organic gardening has wonderfull outcomes!
All it takes is ONE coughing person going through an airport, and then driving to Chicago …
Bonsai On!

I think the consensus from Ryan’s experience and the discussions I’ve seen are that it is one of the things that works in general horticulture, but does not work as well in the small bonsai pot.

I do use compost tea as a fertilizer for my pre-bonsai and have had great results. These trees are growing in the ground however and do not have the same constraints.

I did use compost tea 2x on my trees in bonsai pots and didn’t have any disastrous results, but I have stopped using it since all of the discussion. It just seems like there are better safer ways that are tested and true with bonsai specifically.