Re: [gardeners] Re: Mycorrhiza questions...

Thomas Giannou (
Mon, 19 Oct 1998 12:45:36 -0700

Dear Liz,

You are close to the truth for the most part.  Most of the manufacturers of
commercial mycorrhiza inoculants put together a "cocktail mix" of different
species so that there is a good chance that the plant will benefit from one
of the mycorrhiza present.

According to Dr. Ted St. John, of the tree of life nursery in southern
California, a mycologist and one of the commercial manufacturers of
mycorrhiza inoculants, in a paper he wrote on soil micro-organizims, the
following is an abstract:

"Abstract.-- Ecosystem processes are the combined activities of a variety of
microorganisms.  The most important functional groups include mycorrhizae,
fixers, decomposers, plant growth promoting rhizobacteria,
organisms, builders of soil structure and of protective surface crusts.
These organisms do not reliably disperse to the nursery or to a planting
site.  They require a focused inoculation program from stockpiled top soil
or from pre-inoculated plants. Current technology allows introduction of
mycorrhizae, nitrogen fixers, and pathogen suppressive organisms. Other
functional groups may soon become available commercially."

Mycorrhiza spoors can certainly be present in the vacinity of where an
inoculated plant was planted previously and they will re-infect a new host
plant, but to a lesser degree than adding another charge of inoculant when
new plants are planted each year.  If the gardener has a practice of tilling
the soil each year, then the dispersion of those spores significantly
reduces the benefit that can be achieved from residuals from the previous
years plants.  If you look at the contents of the kinds of mycorrhiza in
inoculants from different manufacturers, you will see that most of them are
using mixtures containing the same species of mycorrhiza.

I'm a results oriented person... not a scientist.... but when I put an
inoculant on a plant I just observe that plant's performance.  There is
performance above ground that is easy to note and there is performance below
ground that is more difficult to note.  I've set up experiments with plants
so that I can observe what is going on with roots as time goes on.  What do
the roots look like at the end of the first, second, third, fourth etc.,
A lot of replication has to be set up to make those observations.  When I
see the root system of a plant take of with an explosion of very fine root
hair structures that normally are not in uninoculated plants.... a process
that fits mycorrhiza and not any other micro-organizim, then there is an
effect.  I don't care which species is causing it... I'm interested in the
fact that the results are present in my garden plants.

With all of the different plants that I have been fiddling with in my
garden,  when I see that proliferation of fine root hairs present then I
always have seen the above ground results which in general fall into these
areas with all of the plants:

1.  The plant appears much more healthy.
2.  Bugs generally are not a problem with those healthy plants.
3.  More is produced by the plant and what is produced is generally earlier
and of much higher quality.
4.  There always seems to be something else that is observable that has not
been noticed in the plant before.  When the level of a plants health is
increased beyond where we find the highest quality plants (according to
non-mycorrhiza nurturing farming practices) there are attributes that have
not been observed before...

Examples of attributes not seen before:

A.  Three months after a lawn is inoculated, a dog can pee on the lawn and
it will not kill the lawn... no brown spot develops.
B.  Three weeks after a lawn is inoculated, a 2 foot by 3 foot 1/8 inch
sheet of steel plate can be left laying on the lawn for 2.5 days.  At the
end of that time, lift it up and the grass has not turned yellow.  It is as
green as the uncovered lawn... just pressed down.  Water it for a short
while and by the end of the day, you can't tell where the steel plate was
laying on the lawn.
C.  Plant Quinault Everbearing Strawberry plants and use 1/4 teaspoon of the
inoculant and those strawberries will produce all summer long such that you
will have to pick them twice a week.
D.  Beefsteak tomato plants were ripe in the first week of August in zone 5.
E.  A single pear tomato plant became over six feet high, ten feet wide, and
three feet in depth and produced tomato's all summer long in zone 5.
F.  Raspberry plants had a root system that looked like a large root ball
two feet wide when dug up and more fine root hyphe hairs were growing out
from that further into the ground.
G.  A 32 inch high 3/4 inch stock green bell pepper plant with 15 peppers on
it as a second crop in zone 5... right at the first frost.

There are about 7 or 8 companies selling commercial mycorrhiza.  What I am
trying to do is get people to recognize that THEY can achieve these
results... I am not here to sell mycorrhiza to anyone.  My purpose in going
to all the trouble to write all this up is inform you people who are better
gardeners than I that there is a better way and you will be seeing a lot
more of this kind of stuff in the market place in the near future.  Montsano
has invested a million dollars with one of the mycorrhiza manufactures.
They are seeing what this stuff can do.  What's really interesting about
this is YOU don't have to be an expert about this stuff.  There are a few
simple things to keep in mind that I have been replicating and having a lot
of success with.  They are no brainer kinds of things that anyone can do.

Here's what I have discovered:  If you grow plants from seed, mix real dirt
in with your potting soil.  Don't use any fertilizer before, during, or
after you plant.  At about 5 weeks use a fertilizer like Biosol 6-1-3.
There are other fertilizers you can use, but you have to be very careful not
to get the phosphorus level above 1%.  You will have the greatest success if
you use the soil where the plant will eventually end up.  When planting, put
about a teaspoon or less of inoculant in the hole and make sure the roots
are touching it.  Water normally.  As the plant grows, avoid disturbing the
soil within one foot of your plant.  No digging allowed!  You will break up
a lot of hyphe and lose a lot of benefit from the plants.  Fertilize
anywhere from 3 to 5 weeks after you have planted.  You only need to do that
once a year.  Water and then go pull weeds if you have any... the mycorrhiza
will keep the soil nice and loose.  You will notice a lot more worms are
present too.

Is this the only way?  I can't say because I don't know all the combinations
that work.  I know the above has worked for me in my garden.  And I have
seen it replicated in a few others.... and all the early girl, beefsteak
etc., tomato's sold here in Spokane's zone 5 have gone nuts with this stuff
this year.

I have been doing my own experiments with this stuff... not that I am any
more qualified to do so, but because it is a lot of fun growing different
things and seeing big differences in the results I used to get with
conventional methods of gardening.

Best Regards,
Thomas Giannou

-----Original Message-----
From: Liz Albrook <>
To: <>
Date: Monday, October 19, 1998 10:32 AM
Subject: Re: [gardeners] Re: Mycorrhiza questions...

Margaret Lauterbach <> wrote:

> I don't think we all have access to a botanist.  At least I don't.
> What did yours say?  Margaret

Mine said that mycorrhiza  are specific to species of plants.
For example, Don in CA is selling the fungi for use with tomatoes --
he has a strain that will grow and work with tomatoes.  It may grow
and work with a few other plants, too.  But there is no general
purpose mycorrhiza that is the answer to everyone's problems or that
will work with every plant.  The last time I read Don's postings they
were testing their strain on many plants but it was sort of a shotgun
type approach -- there's no way to predict which plants will form a
symbiotic relationship with a particular strain.

I have real questions about the usefulness of using any form of these
fungi in an organic garden such as yours -- one in which tomatoes are
planted in the same location year after year.   My own anecdotal
experience is that tomatoes replanted year after year in the same
soil grow exceptionally well.  My guess is that part of that result
comes from soil microbes that become established and flourish year
after year -- not necessarily just a single type of fungus but a
balance of many types of organisms.