The Underground Secret to a Better Garden

Mycorrhizal Fungi: 

Let's talk basics. What exactly is Mycorrhizal Fungi? 


The term mycorrhiza refers to the role of the fungi in the plants' rhizosphere, its root system. (Illustration by Michael Rothman)


A Mycorrhiza is a symbiotic association between a fungus and the roots of a vascular host plant. It's major function being the ability to exchange nutrients between their surroundings and their host plant. A white fungal network called hyphae (resembles roots) is the principal structure for the uptake of many important nutrients in the plant kingdom. The hyphae are only a single cell wide and facilitate nutrient exchanges between the root tip and fungi. While you may see them spread like a web surfacing a decomposing log, they usually remain hidden underground and invisible to us. 

In the Garden

As a gardener, you want to take advantage of this symbiotic relationship that fungi and plants have been developing for millions of years. The key lies in maintaining a healthy community of fungi. One trick is to use caution when dealing with fertilizers and stray away from the use of chemical fertilizers specifically those consisting of phosphorus. Since phosphorus can reach levels that actually discourage the formation of mycorrhizae, avoiding fertilizers with high percentages of the chemical will prevent beneficial microbes from weakening or breaking apart. You can also maintain your soil in prime condition by minimizing disturbances apart from occasional light tilling, weeding and mulching. 

Increasing Beneficial Fungi

One of your main challenges perhaps will be ensuring that this nutrient-infused goodness survives all year round. The fungi that support garden crops are not capable of living or reproducing independently so it is up to us gardeners to ensure we are maintaining and increasing the population of beneficial fungi.

We can start by preventing a decline with simple tricks such as rotating crops within your beds and avoiding empty beds by keeping plants growing at all times. Additionally, you want to take it a step further and consider growing plant rye, oats or hairy vetch. These plants have extensive root systems and readily harbor mycorrhizae. Orchards will serve you well for overwintering fungi because they don't require as much attention and buffer strips of a grass-and-legume blend will help retain fungi.  

The Benefits

    • Improved plant establishment and growth.
    • Dramatically expand access to moisture and nutrients from the soil. 
    • Increased nutrient and water uptake. 
    • Increases efficiency of water use.
    • Drought tolerance. 
    • Improved disease resistance.
    • Assists in weed suppression.
    • Improves soil structure and stability.
    • Improves root growth.
    • More blossoms and enhances nutritional value. 

    Mycorrhizae are the principal structures for the most nutrient uptake in the plant kingdom.

    Are you familiar with Mycorrhizal Fungi? Tricks of your own? What has been your experience? We want to hear all about it! Shoot us your comments below!