Our head grower at Johnson’s Gardens, Jesse McElroy, has been touting the benefits of soil microbes and mycorrhizae for as long as he’s been gardening. He is a firm believer in the merits of organic gardening and his favorite product line of soil amendments is FoxFarm. FoxFarm’s motto is “Don’t Just Feed Your Plants…Feed Your Soil!”. Their products contain an extensive list of beneficial mycorrhizae and bacteria as well as micronutrients. Their fertilizers and soil amendments are alive with beneficial microbes and fungi that help break down organic matter and feed the plant roots.

In 2018 we decided to conduct a trial to see if we could demonstrate the difference between plants grown with Foxfarm’s “living” soil and fertilizers as contrasted with those grown in conventional potting soil and fertilized with chemical fertilizers. On June 23rd, 2018 we prepared two raised garden beds, one filled with FoxFarm’s soil conditioner and fertilized initially with their “Happy Frog” Tomato & Vegetable dry fertilizer. The other bed we filled with a quality bagged potting soil that included slow release fertilizer. We planted both beds with a selection* of tomatoes and peppers.

mychorrhizae microbes soil benefit organic gardening johnson's gardens cedarburg

Maintenance of the two beds was identical, with daily watering and weekly mild soluble fertilizer applications.
The results of our trial have been startlingly dramatic. The plants grown in the soil containing mycorrhizae and beneficial microbes are visibly more robust and display darker green foliage and a faster rate of growth than those grown in conventional potting soil. They have also produced more abundant flowers and are just beginning to produce a large crop of fruit (July 16th, 2018).

These results are not surprising given that, according to the Food & Agriculture Organization of the United States, “The positive role of mycorrhizae in plant production is well documented. The plant response in most cases is due to an increase in effective root area for water and nutrient extraction, since the mycorrhizal hyphal network works as a natural extension of the plant root system. The plant donates carbon to the mycorrhizae in exchange for a greater ability to use native soil resources. Other benefits of the mycorrhizal association are an enhanced protection against pathogens, improved tolerance to pollutants and greater resistance to water stress, high soil temperature, adverse soil pH and transplant ‘shock.’ “

mychorrhizae microbes soil organic gardening johnson's gardens cedarburg

Still, it is impressive to see the evidence with our own eyes.

*We chose Tomatoes ‘Better Boy’ (a classic slicer, one of the most popular tomatoes in the U.S.) and ‘Yellow Cherry’ (slightly less acidic than Red Cherry, with a mild sweet flavor). For Peppers we planted ‘Jalapeno’ (a high yielding chili pepper with medium heat), ‘Pablano’ (a mild chili pepper), and ‘Green Bell’ (a classic sweet bell pepper).