How Does Mycorrhizal Symbiosis Work?
The mycelium (this is the microscopic root system of the mushroom)
grows either around or into the roots of the plant depending on the type
Through chemical processes, the fungus is able to
mine minerals like phosphorus, copper, and zinc from rock and
decomposing organic matter in the soil. These vital nutrients are then
exchanged for sugars that the plant produces through photosynthesis and
that the mushroom can't produce by itself.
The fungal network is extending the reach of a plant tremendously.
Because of the small size of the mushroom 'roots', they can grow into
every nuke and cranny of the soil, extract nutrients and grow much
faster than plant roots. The plant itself could never reach as far with
its own roots and would starve on the way without this beneficial
This is where it gets really interesting:
mycorrhizae can connect to many plants at the same time. Scientists
have discovered that sugars get transported from one tree to another.
Which means that some trees can support other trees that are not able to
produce enough sugars by themselves!
Why Is Mycorrhizal Symbiosis Important For Growing Vegetables?
You might ask why this fungus stuff is so important for your garden.
fact is that most plants thrive much better if they have an association
with a mushroom. They develop a better root system, grow faster and
healthier and are less prone to diseases.
The fungal mycelium also
improves the quality of your garden soil. The soil structure improves
which in turn helps to increase the water storing capacity and nutrient
How Can You Support Mycorrhizal Symbiosis In Your Garden?
In general, the spores needed are in the environment and a germinating
seed will seek the right species for a partnership. Of course, if you
use potting soil out of a bag for starting off your seeds you won't have
the mycorrhizae in there because these soils have been sterilized.
To support the health of your seedlings you can add a commercial product like this at the time of sowing. It contains several species of mushroom spores that will form a mycorrhiza with the plant roots. As a result, your seedlings will be healthier, more drought resistant and they grow faster.
You can also add the spores when you are planting trees, shrubs or vegetables in your garden. Just sprinkle at the appropriate rate into your planting hole.
Plant species that don't form mycorrhizae include Brassicas (like cauliflower, cabbage, etc) or ericaceous plants like heathers. So there is no need to add spores to these plants.
Not disturbing your soil is also important for various reasons.
Every time you dig or till the soil you break up the fungal network that
works so hard to support your plants. No-dig gardening is the answer to
This type of gardening also adds the necessary organic
matter to the soil that will help to support the growth of these
Listen to this interesting podcast by Radiolab. It explains in a fun way how this all works.
What would you like to see next?