Most of the scientific research and widespread publicity about using mycorrhizal fungi to grow plants has been focused on food-type plants, but these beneficial organisms can be put to work equally well on ornamental plants.
Just like food plants, many ornamentals have evolved a dependence on mycorrhizae and have largely lost the ability to efficiently uptake nutrients without the fungi on their roots. Without mycorrhizal fungi, we humans must take on the job of providing all the nourishment to fungi-less plants - usually by continuously applying “plant foods” that mostly wash right through the root zone into underground water supplies.
Keeping a mycorrhizal-dependent plant nourished when it lacks its fungi partnership is difficult and expensive. In effect, the soil must be kept artificially overloaded with nutrients (typically incomplete NPK fertilizers) to the point where even an inefficient root system can suck in enough food to survive. Besides being environmentally harmful, this abnormal loading-up of NPK is harmful and disruptive to soil biology. If there were any beneficial organisms present (and many urban/disturbed soils are lacking in them to begin with), repeated doses of “plant food” can prevent them from multiplying into large populations.
Ornamental plants that would normally use mycorrhizal fungi and nitrogen-producing bacteria to thrive are made dependent on artificial chemical feedings. This almost makes me want to write one of those angry letters to a newspaper that always ends with, “Wake up, America!” but I’m not quite that old and cranky yet.
Turf grass is by far the most egregious example of creating a high-profit industry by making simple-to-grow plants dependent on direct feeding. Grass is ridiculously simple to grow if there are good populations of soil microbes present, and ridiculously difficult/expensive to keep alive and healthy without such organisms.
A biologically-active lawn where mulched clippings are returned to the soil instead of being removed needs virtually no additional input, does not build up thatch, suffers few disease problems, and provides its own soil aeration.
You would think that the chemical fertilizer companies, with all their good knowledge about plant physiology, would realize that they are disrupting the biological processes that would allow plants to grow with very little input. (Pause for thought)
About the only negative I can think of for using a biology-based approach to turf grass is that golf courses do not like the idea of having little mounds of earthworm castings appear on their fairways and greens, but most grass growers should be happy to see such evidence of healthy soil.
I might mention that many golf courses, including some listed in the top 10 nationally, are now using our inoculants. Golf courses are increasingly under fire because of nutrient runoffs and are also faced with the need to fight turf diseases with relatively non-toxic methods for the safety of the golfers. (Ironically, golf courses would probably not dare to use some products that are routinely applied to our food crops, but that’s another story.)
Decorative trees, shrubs, flower beds - all can be very successfully grown without pouring on the great amounts of synthetic fertilizers that we have been instructed to apply. But as I watch the artful TV commercials showing smiling happy people lovingly caressing the fantastic-miracle-lush grass or flowers that Brand X has given them, I can understand why the cash registers at garden centers go ding-ding-ding-ding with “lawn food” sales.
And, as you might imagine, I do a little tooth-grinding when I see homeowners buying soil fungicides that will harm their plant-protective mycorrhizae. To me, this is like fogging your yard or orchard with a general pesticide that kills all insects...including those that would have happily eaten the harmful bugs at no cost. I’m also reminded of a lady who asked what she could do about honeybees that were “invading” the flowering shrub next to her front door. She was spraying them with an aerosol pesticide, but more kept coming! Can you imagine how she would have panicked if she learned there was fungus on her plant roots?
To learn more on this topic, look at all the mycorrhiza studies that have been done on food plants and remember that the same symbiotic logic applies to ornamentals...and wake up, America!
Cheers, my friends.
President, BioOrganics, Inc