Jeff Lowenfels, the author of Teaming with Nutrients and Teaming with Microbes, has delivered his 3rd book in the Teaming trilogy series, Teaming with Fungi . It’s a very informative read, as were his previous books.
Mycorrhizal fungi may be the least understood aspect of gardening. Years ago, fungi were thought to be bad, very bad. Hence, the plethora of pesticides which were developed to kill every imaginable form of it. It’s been long known that fungi are essential to the decomposition of wood and other plant material. But scientists have more recently discovered that mycorrhizal fungi are highly beneficial for nearly all plant life – Teaming with Fungi explains that they in fact form a symbiotic relationship with 80-95% of the plant species on earth. These fungi have also been found to be imperative for the health of your soil.
See my previous post, what are mycorrhizal fungi?
When I first read about beneficial mycorrhizal fungi, I was fascinated. Scientists found that the fungus colonizes the root system of a host plant, increasing the plant’s ability to uptake water and nutrients. In exchange, the plant provides the fungus with carbon from photosynthesis, which the fungus cannot manufacture on its own. That is quite a remarkable interdependence.
But according to Teaming with Fungi: The Organic Grower’s Guide to Mycorrhizae , it gets more complicated than that: scientists have now discovered that there are specific mycorrhizal fungi for each plant species. Grasses for instance, use different mycorrhizas than pine trees. In fact, nearly every growing plant, from deserts to rainforests use these beneficial fungi to uptake nutrients, increase drought resistance, increase resistance to root disease, grow fruit earlier in the season, and to generally grow bigger and healthier. It has also been found that these fungi reduce the need for fertilizer, particularly phosphorous, as mycorrhizas add phosphorus to soil and make it available to plant roots.
According to Lowenfels, to some degree, mycorrhizal fungi exist in all native soils. But that’s the problem – much of the soil on your property is not native and has been trucked in from elsewhere. During the soil harvesting process much of the fungi were probably killed, or it may include mycorrhizal fungi which are of no use to the species growing in your garden. So a gardener needs to take measures to increase the amount of fungi around plant roots, especially on new properties.
How beneficial are mycorrhizal fungi? In agricultural studies:
- Asparagus inoculated with arbuscular mycorrhizal fungi grew taller with more crowns and shoots than control plants.
- Basil showed growth increases of 400%, with leaves showing the ability to adjust to drought.
- In Cannabis production, mycorrhizal fungi have been shown to increase growth and produce more flowers of higher quality.
- In corn, root tissues increased between 35-98%.
- In grapes, inoculated vines showed increases in dry weight, nutrient uptake and height.
- In potatoes, the number and size of tubers increased almost 50%.
- In tomatoes, mycorrhizal fungi inoculation resulted in increased height, plant growth and weight. Tomatoes also survived nematode infestation.
- In daffodils, inoculated bulbs showed improved flower yield, stalk strength and quality.
- In marigolds, inoculated seeds showed faster growth and higher quality flowers.
- In petunias, inoculated plants had higher reproductive growth and a threefold increase in vegetative growth.
- In lawns, grasses inoculated with mycorrhizal fungi are generally healthier, contain more chlorophyll and grow denser, healthier root structures.
Mycorrhizal fungi have also been shown to be extremely beneficial in restoring damaged soils and forests.
Note that compost contains no mycorrhizal fungi, as there are no live roots to support mycorrhizal growth and the heat which breaks down your yard waste into compost destroys any mycorrhizae which were initially present.
How to add the proper mycorrhizal fungi to your garden to benefit your plants.
As we learn in Teaming with Fungi , specific mycorrhizal fungi bond with specific plants. As you have dozens of species of plants in your garden beds, it would be nearly impossible for you to find and inoculate the specific mycorrhizal fungi for each of your plants. So the best way to build these populations is to buy a mix of mycorrhizal propagules with multiple species and add it around the roots when you plant, or inoculate the soil around the roots if it’s already planted. It’s also a great idea to add mycorrhizal propagules to seed starter mixes (which are sterile) and potting mixes to encourage your container plants and seedlings to thrive.
Buy on Amazon: Endo Mycorrhizae (4 Species, 1LB Package)