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Weed Tea - Turning weeds into friends

If you've followed the saga of my weed problem, and how I'm trying to turn the weed (I'll call it Trans for short,(we are on close terms)) to my advantage. You will know that I had to rely on others, much to my embarrassment, it should be acknowledged, to identify what it is that has been causing me such angst. 

I found that drowning the bugger in a sealed drum for over six weeks took care of it and produced brown lifeless mulch for the garden. The remaining brown liquid, we'll call it weed tea, was left behind but due to it being produced in an anaerobic way, according to Dr Elaine Ingram, it would be problematic to use it like that on the garden. So I've been applying myself to the task of introducing oxygen to the liquid. Elaine Ingram advises that I should pump oxygen into the drum via a fish tank type of pump, which we all know pumps bubbles of air in at the bottom and this then percolates it's way upward from there. She also states that the smell of an anaerobic drum of liquid will be very strong, but as my nose is about as reliable as my weed identification skills, I couldn't tell whether the liquid was indeed "off" or not. So the above photo shows my solution. What you see is the top of my 44 gallon drum, an old pump is spraying liquid from the bottom of the barrel onto the water at the top. You can see the white foam being created.

My questions to you all is, "will this introduce air (oxygen) to the mix", and if it does how long do you reckon I will need to keep this going for? At this point I need to acknowledge that it was my wife Brenda who's idea it was to turn the sprinkler upside down, I had constructed something on top, but once again I was wrong, (ouch).

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Comment by Elaine de Saxe on June 17, 2015 at 12:24

Not in a position to discuss the physics, Andy … but if you have an airstone going 24/7 it must do something positive. They are used to provide oxygen for aquarium fish so I make the assumption (without any idea of how to prove it) that airstones bring in air and oxygen is part of air.

I'm interested to read a proper scientific reason.

I wouldn't be querying Elaine Ingham yet I do read variations on the theme of providing food and air for microbes. It's likely there are many systems for making weed/compost/whatever tea and they all work to a degree. Without the laboratory facilities to see the organisms, we amateurs are flying blind.

Comment by Andrew Cumberland on June 17, 2015 at 11:51

Anerobic is often stinky Rob, otherwise neither bad nor good.  The microbial stuff is what will help break the tea down into a useful form of liquid compost.  

Oh... and let me correct a typo last night: Oh, don't tell anyone, but the air from the aerators do NOT actually add oxygen to the mix.  They are used to break the surface tension which lets oxygen in.  You can do it just as well with your water hose outlet on the bottom.  

Comment by Rob Walter on June 17, 2015 at 8:59

Hmm, Elaine Ingham seems to be advocating a very particular kind of "compost tea". It's all about having healthy organisms that can cling to leaves and enrich the soil biota. Is it so bad to have anaerobic decomposition?

I've just started with weed tea, but my focus is on ensuring that I am not having to import nutrients to the garden because I'm exporting nutrients from my garden by throwing out weeds, the microbial stuff is less important to me because I do believe that sorts itself out given plenty of mulch and an organic approach.

The reason I've just started with weed tea is because when I tried about two years ago, I started by putting a huge, unproductive Brussels sprouts plant in a bucket of water. Within a week the smell was overpowering all through the garden, occasionally reaching the house. I thought it was because of fact I'd used a mature brassica which is so packed with smellifying compounds that even just rotting on the ground it would smell pretty bad.

Comment by Andrew Cumberland on June 16, 2015 at 21:50

The usual system is to aerate from the bottom with an air pump.  The advantage is that it moves solids on the bottom.  What you are doing is pretty good - but you do run a risk of anerobic silt at the bottom of your drum. I'd move your current hose to the bottom and you've solved the entire problem!

Oh, don't tell anyone, but the air from the aerators do actually add oxygen to the mix.  They are used to break the surface tension which lets oxygen in.  You can do it just as well with your water hose outlet on the bottom.  

Comment by Roger Clark on June 16, 2015 at 20:39

Yes, Susan I'll photo this tomorrow arvo and post it, it's basically just a series of threaded fittings to reduce the thread size down to a normal hose size.

Comment by Elaine de Saxe on June 16, 2015 at 20:11

I've used a solar then a mains-powered airstone arrangement. This works OK in a 10L bucket but would need to be much bigger for a bigger drum.

That froth resembles the froth you get when cultivating microbes from compost by adding some molasses to feed the microbes. How long - well the people who write about growing microbes reckon on 24-48 hours before the microbes kill themselves with their own excreta or run out of food. Whichever comes sooner.

There is info out there on home-made microbe soup and there is a proper phrase to describe it too but it's escaped my memory just now. 

Comment by Susan on June 16, 2015 at 19:09

Would you be able to put a picture showing how your pump is connected?  I'm not very handy and I'd be interested to see this.

Comment by Lissa on June 16, 2015 at 18:58

That's a nifty idea for oxygenating Roger and a good use for the Trans. You can't make it into a hard narrow spray can you? To bite a little deeper into the mix.

I've just been using the hose on hard to do this lately but my son complained of the smell so I obviously wasn't doing it often enough. I have a poor sense of smell. I bought a new little pump but the end bit doesn't seem to create enough of a flow to do the job.

I tipped the whole lot out on the adjacent pawpaw plants the other day - they love it, anaerobic or not.

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Vetiver grass helps to stabilise soil and protects it against erosion.  It can protect against pests and weeds. Vetiver is also used as animal feed. (Wiki.)

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