Effects of Fulvic Acid, Microbes and Timing

We know nutrient management is critical for potato production, but do fulvic acid and microbes live up to the hype?

Published online: Feb 08, 2018 Articles, Fertilizer
Viewed 4821 time(s)

Effective management of nutrients is critical for potato production, as tuber yield and tuber quality are directly impacted by source, quantity, and timing of nutrient applications.

AgroLiquid’s PRIMAGRO line includes C-Tech, which contains organic matter, live strains of beneficial fungi, bacteria, microbes, and soil-activated chelates that help better hold nutrients in poor soil types, potentially improve seed application safety, release nutrients within soil solution, promote biological activity and help increase overall plant health. C-Tech also contains 3.50 percent fulvic acid.

In this experiment, C-Tech was applied at planting and at hilling to Snowden potatoes. The objective was to evaluate C-Tech’s impact on potato yield and tuber size distribution. Other treatments in this trial included PRIMAGRO P, as an extended delivery of available phosphate throughout the growing season, PRIMAGRO K, as an advanced, high-efficiency potassium product containing sulfur, and HIGH NRG-N represented the source of nitrogen.

Prior to planting date (May 12, 2017):

  • Comprehensive soil sampling; herbicide applications; soil tilled by cultivator to a 6- to 8-inch depth; seedbeds rototilled. Sulfate of potash (0-0-62) broadcast pre-planting at a rate of 300 pounds per acre in all the treatments.
  • Surface drip irrigation provided supplementary and sufficient water requirements to the crop.    
  • A protective and proactive program of pesticides and herbicides was carried out during the course of this experiment to maintain a healthy growth of the potato.


  1. Researchers witnessed a remarkable growth of “Snowden” potato due to the application of C-Tech and PRIMAGRO.
  2. The C-Tech application, which is a specialized formulation of carbon and biological agents, proved to be an added value to increase the potato yield at side dressing or at hilling.
  3. PRIMAGRO P and PRIMAGRO K helped increase the potato yield, but not to the level of application of C-Tech.
  4. The results demonstrate that potatoes, which have a relatively shallow root system, often require substantial nutrient input, which can be productive when managed properly to maintain tuber productivity and quality