Compost Teas: 24 hour, EM, IM, BD & fermented plant extracts

["Soil Foodweb, Inc." <info AT soilfoodweb.com>]

Respone to Scott Maleny and Carole Eddingtion's questions/comments

Compost Tea pH -  What is the right pH for tea?

It depends on the plant to which you will apply the tea.  A pH of 6.5 to 7.5 
is good
for plants that need a one to one ratio of fungi to bacteria.  But it may not 
be
correct for blueberries.  They need, oh, pH 5.5 to 7, just as most fungal-soil
loving plant.  Will you significantly affect soil pH if you put on a tea with 
a pH
of 7.0?  Maybe.  Probably not.

What's the right pH for pasture grass in Australia?  Probably same as the 
soil pH
the plants are growing in.  So, maybe a pH 8.5 is what you want.

Why do we worry about pH?  Because if pH is WILDLY off, you will kill the 
organisms
in the compost.

How much wiggle room is ok?  As long as there is good life in the soil, 
plants do
not particularly care about pH as long as pH is below 10 and above 4.5 
(calcium does
strange things with clay at higher or lower pH).

But pay attention to what I just said.  As long as there is good life.......

A good soil foodweb buffers pH, brings it back into the right pH rapidly.  In 
your
tea, or in your soil.

Right pH for who?  Themselves, the organisms in your foodweb, of course.  
That's why
the soil foodweb needs to match the needs of the plant.  (I feel like Spock
explaining why he let himself get killed... The needs of the one outweigh the 
needs
of the many...)

The right ratio of fungi to bacteria maintain soil pH correct for the plant.  
And
the form of N. And P, S, K, Ca, Fe, etc, etc, etc.

Let the critters do the work in the soil for you......
----------
How do you know if the pH in your tea maker IS NOT right for the organisms in 
your
compost?  Test your tea.  Do you have active bacteria and fungi in the tea?  
If yes,
then don't worry about the pH.

If you don't have the biology in the tea, then consider that you have water 
that
isn't right for the organisms in your compost.  You have to do something 
about it.
OK, but what?

In your tea maker, after getting rid of the chlorine (citric acid complexes
chlorine), add your compost.  Compost itself will buffer pH because compost 
contains
lots of acids and bases.  Add your molasses, your kelp, your whatever, and 
then
check pH.  Let the tea brew, and take a sample.   Send the tea in to test for 
the
life in the tea.

If your don't have enough organisms in the tea, and pH was way off relative 
to your
soil, then you need to find another water source, or start playing games with 
the
water, which is not fun.

Why do people put citric acid into the water?  To complex the chlorine 
usually.  Not
much citric acid, or you will outstrip the buffering capacity of the water.
Buffering capacity means the ability of the water to absorb the hydrogen ions 
from
the acid without the water changing pH.

What Carole describes, adding acid and then the water comes right back to pH 
8.9, is
water with a huge buffering capacity.  There is so much bicarbonate in the 
water
that even with added acid, the pH starts to rise within a few hours.  They 
have
shown that the tea doesn't have adequate organisms if they don't reduce the 
water's
pH.

We've been doing some anecdotal work (that's means this is not scientifically
replicated yet, ok?) with phosphoric acid and liquid fish stabilized with 
phosphoric
acid.  In these situations with very highly buffered alkaline water, how much
phosphoric acid do you add?  Monitor pH while you add the acid.  Once you 
reach
neutral, or as Carole talked about, once you reach as low as you care to go 
based on
previous testing, you stop adding the acid.

You can call your water treatment plant and ask them what is the pH of the 
water
coming from the plant.  Ask them what to use to neutralize it if it is too 
alkaline
or too acid.  Do the neutralization BEFORE you add the fungal or bacterial 
foods in
your tea, before you add the compost.

Check the tea after brewing to make sure everything survived.

Clearly we have more to do to understand this, and some help from water 
chemistry
people would be a good idea.

There must be something that gets rid of bicarbonate from water once and for 
all,
without having to drip in the acid to keep the alkaline bicarbonate from
re-forming.  Aerating the water is critical here too, because the sodium, 
potassium
and/or calcium carbonate/bicarbonate must reform as the organisms in the tea 
respire
CO2 as they grow.  That's why the pH rises again in Carole's example.  
Something is
not right about the water, but I don't have time to focus on this question and
figure it out.

Anyone know a good water chemist?  Can you share their thoughts with the 
group?

Elaine Ingham
President, Soil Foodweb Inc.