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Could adding soil probiotics be beneficial for business?

Greenhouse owners are always looking for new ways to increase yields quickly, as well as their return on investment. But soil probiotics and microbial fertilizers are not new.

Known as ‘biofertilizers’, their commercial history began with the launch of ‘Nitragin’ in 1895. This product contains nitrogen-fixing rhizobia known as Rhizobium leguminosarum, originally isolated from the roots of legume crops then cultivated for application. This beneficial microbe would form a ‘symbiotic relationship’ with the plant, increasing the number and size of nitrogen-fixing nodules on the roots to increase nitrogen availability in the plant.

Since then, the industry has been improving ways for nutrients in the soil to be better usable by plants. Because crops have different nutritional needs and relationships with different microbes, microbial fertilizer formulations have to be tailored towards different types of greenhouse crops. It’s not a new concept for many field crops, but adapting this technology to greenhouse operations helps balance many of the shortcomings of conventional chemicals, while continuing to improve soil fertility and productivity.

What are soil probiotics?

If soil is like the stomach of a plant, then biofertilizers are “probiotics for the soil.” Nutrients can be hidden in plain view, unavailable to plants because they are locked up as insoluble minerals or in slow-to-decompose organic matter. When biofertilizers are applied to soil, preferably at planting, the beneficial microbial populations come to life, begin multiplying, and produce a range of enzymes and other compounds that help to break down organic matter, solubilize minerals and fertilizers, and conserve soil moisture.

“Without vibrant beneficial microbes in the soil, plants are unable to reach their full potential – they cannot use the soil’s natural fertility or efficiently absorb added fertilizers,” says Simon Neufeld, director of Soil Management at Earth Alive Clean Technologies. Soil contains a vast diversity of microbes, and scientists comb through the diversity looking for specific microbial strains that enhance plant growth. Biofertilizers can stimulate natural microbe communities while also adding functional natural microbes that have been selected from the soil.
 

Different forms for different uses
Biofertilizers are easy to use. Coming in liquid, granular or powder forms, the method of application depends on their concentration and form. Granular forms are generally applied dry, either alone or in combination with other amendments. Liquid products can come premixed or concentrated, and must be applied with water. Powder-based biofertilizers are more versatile, because they can either be mixed with water and drenched around the root area, or mixed directly into the growing media. A soluble powder formulation can also offer better shelf stability and better ease of mixing with water, for application through an irrigation system or spraying equipment.

For best results apply early in the season, ideally at the time of planting, to give the microbes time to settle in, multiply and fulfill their function.

The advantages of soil probiotics
“Many greenhouses grow in soilless media, which can be deficient in native biology,” explains Neufeld. “Plants grown in soilless media can thrive when growers provide them with functional probiotics.”

“I realized that if I can use a product that enhances soil, boosts fertilizer and lowers my plants’ water needs, I can cover more ground with fewer products at a lower cost per plant,” said Benjamin Thauvette, owner of Les Serres Chlorophylle greenhouse in Quebec. 

Flowers treated for Mother’s Day were on time, in full-bloom and showed outstanding colours, said Thauvette. “And vegetable plants fought off diseases and pests better than those that were not treated. So in the end, we had more plants for sale and less headache. The results we’re beyond my expectations.”

According to Neufeld, tomato and pepper greenhouse growers using microbial fertilizer saw taller vines, more fruits, and higher yields. Roses and other ornamentals grown in greenhouses have also responded very well, with increased production of new canes, greener leaves, more and longer flower stems.

 
What to consider when purchasing a microbial fertilizer
“Growers should think about how their production methods support or inhibit biological activity in the root zone of their plants,” explains Neufeld. “Intensively managed growing systems have to improve not just the physical and chemical environments for the plants, but also the biological environment.” It’s important that plant roots are surrounded by beneficial microbial activity throughout the growing cycle, he adds, to ensure that plants have access to the resources they need to maintain growth.

For organic growers, OMRI-listed biofertilizers are approved for organic use, containing no genetically modified organisms or synthetic chemicals. They can also be used in conventional growing, allowing the grower to use less fertilizer to gain the same or better results.
 

Earth Alive Clean Technologies is a developer and distributor of microbial products for agricultural and mining sectors. Visit www.earthalivect.com