Most biological fertilisers don’t fail because they’re ineffective.
They fail because they’re misused.
Most often, farmers apply biologicals like they do chemical fertilizers which is same timing of application, same method of application, and same mindset when applying. Since biological fertilizers are comprised of live microorganisms, if handled improperly before application, they will die before reaching the root zone.
Research published in npj Sustainable Agriculture confirms what has been shown through field-level experience that performance of biological fertilizers varies significantly based on environmental conditions, crop systems, and application practices while the science behind biologicals works; the management of biological products does not always provide the best results.
Thus, this isn’t a problem with the product; this is a problem with practice.
Best practice use of biological fertilizers is important. There is little choice than to practice them in the best way possible.
Test Your Soil First. Always.
Here is the first rule that most farmers fail to follow: never use biological fertilizers in a blanket fashion. A study published in Frontiers in Plant Science verifies that some soils have too much or too little of certain nutrients, and thus soil nutrient analysis is crucial before any biological fertilizer is applied. Research conducted in De Gruyter indicates that a nutrient management plan that carefully targets fertilizer application according to the actual needs of the crops will always beat blanket application strategies.
Soil analysis helps identify the existing microbial communities, pH, and nutrient levels that will favor the growth of certain strains of biological fertilizers. Analysis by ScienceDirect indicates that soil pH is a major factor in microbial diversity, taxonomy, and functional gene enrichment, implying that applying the fertilizer in the wrong pH conditions will simply kill the microbes before they even have a chance to colonize.
Timing and Placement Are Non-Negotiable:
Using biological fertilizers incorrectly, at the wrong stage of growth or with incorrect methods renders them unable to work effectively. Research on fertilizer application methods from ScienceDirect has shown that when surface broadcast applied, you can expect losses from the fertilizer of up to 50%. However, if the fertilizer is applied deep into the soil or directly where plant roots are located (root zone), higher uptake and efficiency is achieved.
Research published in ResearchGate has found that seed priming with beneficial genetics specifically Serratia marcescens resulted in an increase in the amount of seeds that germinated by 56.88% versus non-primed seeds. This demonstrates that treating seed before planting is one of the cheapest and most effective ways to apply biological fertilizer.
According to npj Sustainable Agriculture, biofertilizers need to colonize the rhizosphere, rhizoplane, or root interior in order to provide nutrition; therefore, how fertiliser is applied will also determine if colonization occurs.
In conclusion, applying fertilizer in small amounts (split application) will produce greater results than one large application. Studies in PMC support this, indicating that multiple applications also provide a consistent population of microbes throughout the duration of the crop growth cycle, while preventing significant nutrient loss associated with rain events.
Never Mix with Chemicals Carelessly.
This is where the error in biological fertiliser investment lies, combining microbial inoculants with chemical pesticides, fungicides, or high concentration fertilisers that kill living organisms. According to a study in De Gruyter, combining biological methods with precision agriculture practices multiplies outcomes, but the wrong chemical mixtures completely negate microbial life.
Research shows that farmers in sub-Saharan Africa get only 50 cents back per dollar invested in fertiliser productivity because of inefficient fertiliser application, a problem that can be directly solved by correct biological fertiliser practices.
Store Correctly or Lose Everything.
Since biological fertilizers involve living organisms, storage is responsible for the destruction of viability faster than any other factor. According to ResearchGate, microbial fertilizers have certain requirements for temperature, humidity, and light to ensure the viability of the colonies during storage and transportation. Research indicates that products stored in hot warehouses or under direct sunlight lose viable organisms faster than they reach the fields.
Why Best Practices Determine Everything?
Because research in De Gruyter confirms that inefficient fertiliser practices lead directly to economic losses, environmental degradation, and food insecurity. Getting biological fertiliser practices right isn’t optional, it’s the difference between investment and waste. Biofertilizers absolutely work under the right conditions. But wrong timing, placement, mixing, and storage make them fail every time.
