For many years, chemical use and high levels of fertilization have been widely accepted as the best practice by farmers, landscapers and home growers. Even if used correctly, the margin between safe use and phytotoxicity (harm to the plant) is often very small. There are also dangers to animals and humans from the use of chemicals themselves. Despite these problems, the lack of effective alternatives did not leave growers many choices.
More recently, however, farming growing practices are beginning to change. More growers are completely eliminating the use of chemicals and greatly reducing the use of fertilizers. These changes have been brought on for many reasons; one reason is the increase in scientific research demonstrating the toxicity of many of the chemicals being used by growers (such as increases in Parkinson’s Disease1 and cancer rates2,3 or lethal algae blooms in our waters4,5).
A bigger driver for the change is the development and/or wider recognition of effective natural or organic products for increasing yields and treating pests and diseases. One of the greatest developments in this area has been the increased recognition and use of beneficial bacteria in agriculture.
In most cases, the use of beneficial bacteria can lower fertilizer and water use by 50%, and completely eliminate chemical use with better results (20% increases in yields are standard). In addition, there is no toxicity to humans and animals. In fact, the use of bacteria has shown to cure depression6 and gastro-intestinal disorders7, and overuse does not have detrimental effects for the plants.
Beneficial microbes have co-evolved with plants over millions of years. In fact, it is now known that plants and symbiotic microbes actually have elaborate systems of communication. For example, a plant will secrete substances into their root zone to attract beneficial Bacillus strains when the plant is under attack by pathogens. Plants will also exude beneficial substances, including sugars, to feed beneficial fungi and bacteria.
In exchange, bacteria will produce plant hormones (such as auxins, gibberellins and cytokinins) to stimulate plant growth, as well as fight pathogens. Beneficial organisms will also help plants better utilize fertilizer and nutrients. Some strains help solubilize phosphates, making them more available. Nitrogen-fixing bacteria can take nitrogen out of the air and fertilize a plant naturally, while certain types of bacteria can convert higher nitrogen forms (ammonia and nitrites) into nitrates, which is the only form of nitrogen that a plant can use.
By building up the numbers of these bacteria, fertilizer can often be reduced 50% while making the uptake and retention of that fertilizer even more efficient than adding higher amounts. Bacteria can also travel through the transportation systems of plants (the xylem and phloem), thus acting as a natural transportation system for compounds and substances, as well as a mobile immune system that will help to suppress pathogens.
“The Earth is not sterile, nor was it meant to be”. Growers are just beginning to understand the extent to which plants and animals depend on beneficial bacteria. Incorporating beneficial bacteria into your growing practices will increase your plant health and yields, as well as lowering your chemical and fertilizer use.
About the Author
Joseph Maggazi of Grow Home Organinics, LLC is a contributing writer for Mike the Gardener Enterprises, LLC. Grow Home is the maker of Quantum Growth, a consortium of over 20 strains of beneficial bacteria that perform all of those above plant health functions.