Master Gardener Jim Janke had a question about a fungus, Mycorriihiza, so he decided to conduct an experiment last year to find out more information about this mysterious fungus.
Mycorrhiza is supposed to provide better absorption of water and nutrients from the soil, a 400-percent increase in seedling growth, increased drought resistance, less need for irrigation, enhanced plant health, better disease resistance and more. However, Janke’s research showed otherwise.
Mycorrhiza fungi have existed in nature for millions of years and are everywhere. They form a symbiotic relationship with plant roots that is beneficial to both the fungus and the plant. Roots grow better, so the plant thrives; the fungus feeds on sugars produced by the plant.
Janke bought a 2-pound bag of endomycorrhizae inoculant in granular form for about $20; powders, solutions and pre-treated planting media were also available.
Just before planting, he added 6 tablespoons to each large planter, incorporating into the soil about three inches deep (i.e., in the root zone). Two planters in the same location were not treated for comparison purposes. The 2-pound bag was enough to treat eight or 10 large containers.
The label warned against using fungicides with this product, as they might kill the good fungus. Thus, mycorrhiza might not be good in the tomato bed if you use a fungicide there to treat blight.
The label also warned against fertilizing with phosphorus; Janke used a slow release fertilizer that is relatively low in that element.
While this trial was admittedly not even close to being statistically significant, the results were disappointing. There was basically no difference in growth or flower production between the treated and untreated containers.
Yet the claims are so intriguing that Janke said he will try this again, next time treating plants in the ground instead of in containers, and also treating some seedlings.
More research will need to go into this topic, Janke said. The solution might be that powders or solutions would be more economical than the granular material.
Jim Janke is an Extension Master Gardener Volunteer in Haywood County. For more information call the Haywood County Extension Center at 828-456-3575.