The science of symbiosis

From better root development to enhanced stress tolerance, mycorrhizae play a vital role in plant health.


Healthy plants begin with robust roots. To give those roots a boost, begin with an application of mycorrhizae. These specialized fungi colonize plant roots and extend far into the soil to acquire resources that plants can’t access alone, beyond the nutrient depletion zone, and in forms that are tightly bound and not available to the plant. 

“Essentially, mycorrhizae are an extension of a plant’s root system,” explains Anissa Poleatewich, the Senior Manager of Product Development at Mycorrhizal Applications. “Mycorrhizae help plants obtain water and nutrients, and help plants tolerate abiotic or biotic stresses because of those associations they form.”

These symbiotic associations between mycorrhizae and root systems also lead to enhanced nutrient use efficiency and enhanced water uptake, she adds.

“The mycorrhizae will remain in a symbiotic relationship with the plant for the entire life of the plant. The plant and the fungi are both giving and taking something,” she says. “The plant is photosynthesizing and producing sugars that it gives to the fungus, and in return the fungus gives water and nutrients.”

Because they’re inhabitants of the soil, the fungi help build soil structure, she adds.

“They help form micro- and macro-aggregates that help reduce erosion. That helps with moisture content and helps prevent water loss and nutrient leaching.”

Mycorrhizal Applications offers products in granular or suspendable powder form. Products can be incorporated into growing media, applied directly to roots during transplanting, drenched, sprayed, applied as a root dip or plug dip, or injected into the root zone of existing plants.

As long as roots are present, the mycorrhizae can do their microscopic duties. The earlier a grower applies the fungi, the more benefit the plant receives from the symbiotic relationship.

Therefore, young plant growers can apply the fungi once roots form, or finished growers can make applications at the sticking phase or when shifting up plants to a larger container.

“Mycorrhizae are great for reducing transplant shock,” Poleatewich says. “Mycorrhizae help plugs avoid transplant shock and improve survival rates.”

It takes about four weeks to establish that symbiotic relationship and eight weeks to see results.

The entire supply chain benefits and the green industry can tout the use of mycorrhizae as a selling and marketing advantage.

“If a plant is treated at a greenhouse or nursery, then transplanted into a customer’s landscape, the mycorrhizae will also be transplanted with the plant and will continue to help the plant thrive for its entire life,” says Katie Gustafson, marketing and communications manager at Mycorrhizal Applications. “That plant is going to put up with more stress so the homeowner is going to have more success with that plant over its lifetime.

“And for retailers, that plant will arrive healthier and more stress resilient. For example, if plants aren’t watered as often as they should be – the mycorrhizae will help the plant to mitigate that stress. Overall, the plants are going to be more resilient.”

In addition, mycorrhizae from Mycorrhizal Solutions are OMRI certified (Organic Materials Review Institute), an international non-profit that determines which products can be used in organic production under the USDA National Organic Program.

“With one in three respondents to the National Gardening Survey reporting that they are choosing to buy mostly or all organic products, an OMRI listing is a top selling point for many customers,” Gustafson adds.

For more: mycorrhizae.com/how-it-works/

April 2024
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