MYCORRHIZAE
Supplementing Mycorrhiza
“mycorrhizae
are
like soil probiotics that help
plants fight off diseases.”
84
Maximum Yield USA | January 2017
You can now buy the spores of mycorrhizal fungi in all
good garden centres and simply sprinkle them on your
plants like any other plant growth stimulant. But it’s
easy to waste your money. It’s not always necessary to
add more to what’s already in the soil. For one thing, in
normal, fertile garden soil, countless mycorrhizal fungi
already live in harmony with the plants which grow
there without you having to open your wallet at all.
Soil is more delicate than it looks, though, so it’s quite
possible to ruin your free supply of mycorrhizal fungi
with clumsy gardening. Mycorrhizae only thrive in a
healthy, undisturbed soil ecosystem in which they can
form their filigree webs without some gardener coming
along and trashing them with a spade. Many traditional
gardening practices often do untold harm by breaking
these fragile relationships between soil organisms. For
example, autumn digging lays waste to soil ecosystems
so thoroughly that they can take the next year to recover
(by which time you’re on your way over with the spade
again). And phosphorus-rich fertilizers can actively
suppress mycorrhizal activity.
So, look after your naturally occurring mycorrhizae
and garden light upon the earth. Avoid digging wherever possible. Instead of the traditional end-of-season
soil turning, just clear spent crops and then mulch
thickly with organic matter instead. The worms pull
it into the ground for you, leaving mycorrhizal relationships intact. This no-dig system naturally aerates
and feeds your soil, so there’s no need to add artificial
nutrients as well. Slow-release organic fertilizers, like
pelleted poultry manure or bone meal, add naturally
occurring minerals gradually to the soil, so you can
continue to use those, but with mycorrhizae intact, your
plants access those minerals more efficiently, so cut
down the amount by about 20 per cent.