The research was carried out between March 23 and April 1, 2026, inside the KK2 experimental growing facility operated by Csillagváros Kft. The cultivation system used a static, aerated, non-recirculating Kratky/DWC configuration, allowing direct observation of nutrient solution dynamics and root zone responses.
Four microgreen species were included in the trial:
The tested treatments consisted of:
Beyond yield measurements, the trial also focused on operational stability, nutrient solution behavior, plant development characteristics, and nutritional parameters.
Maintaining stable pH values is one of the most important aspects of hydroponic crop production, as fluctuations can directly affect nutrient uptake efficiency and root health.
Throughout the cultivation cycle, Humikal treatments displayed pH behavior similar to the untreated control solution. The granulated formulation, in particular, maintained a more balanced pH profile up to harvest compared to other treatments, while the Humin Garden+ reference shifted the nutrient solution more strongly toward alkaline conditions.
This observation may be highly relevant for commercial hydroponic operations where constant pH correction requires additional labor, acid dosing, and system management. The initial results suggest that Humikal products may integrate into hydroponic nutrient programs without creating excessive pH instability.
Electrical conductivity is a central parameter in hydroponic cultivation because it reflects nutrient concentration and dissolved salt content inside the solution.
According to the measurements collected during the study, Humikal products caused minimal deviation in EC values relative to the control treatment. This can be particularly advantageous in precision fertigation systems where EC-based dosing and monitoring play a major operational role.
Compared to the Humin Garden+ treatment, which produced noticeably elevated conductivity values, the Humikal formulations appeared more compatible with stable nutrient management strategies.
For automated indoor farming systems, predictable EC behavior may improve dosing consistency and simplify nutrient solution control.
One of the key evaluation criteria was the total harvested biomass generated during the one-week cultivation cycle. Measurements were collected from a combined growing area of 0.72 m² across all four tested species.
The most significant increase was observed with the Humikal granulate treatment, which achieved approximately 23–25% greater total biomass compared to the untreated control.
The liquid Humikal treatment also produced moderate biomass improvement, while the Humin Garden+ treatment generated the highest total fresh weight overall.
In hydroponic production systems, however, productivity alone is not sufficient for practical applicability. Operational factors such as residue formation, cleaning requirements, nutrient stability, and compatibility with cultivation infrastructure are equally important.
Developmental indicators and leaf formation data revealed particularly interesting results in sunflower microgreens.
Both Humikal treatments and the Humin Garden+ reference demonstrated more advanced growth stages compared to the control group. These findings suggest that future production cycles may potentially be shortened by approximately one day.
Within a standard 7–8 day microgreen cycle, such a reduction could improve production efficiency by up to 12.5%.
For indoor farms and vertical growing systems, shorter production cycles may directly increase shelf turnover, cultivation capacity, and economic performance.
Microgreens are often valued for their concentrated mineral and nutritional composition. Laboratory testing in this study evaluated 12 different elements, including:
The analytical report indicated that several Humikal treatments contributed to mineral levels approaching or reaching EU nutritional claim thresholds associated with “source of” labeling for calcium, potassium, and magnesium.
This may represent an important advantage in premium food production and functional nutrition markets where nutritional density plays a major commercial role.
Food safety remains a critical consideration in all indoor and hydroponic growing technologies.
Heavy metal analysis performed during the trial showed that most measured values remained below detection limits.
Nickel and cadmium were detectable only in sunflower samples, but concentrations remained safely below concerning thresholds and did not indicate food safety risk.
These findings support the suitability of the tested system for controlled-environment food production applications.
The study also provided valuable operational insights regarding product handling and system integration.
During preparation of the granulated Humikal formulation, a small amount of sand-like insoluble residue remained after mixing. In the DWC setup this created only a fine sediment layer at the bottom of cultivation trays and did not interfere with plant growth.
However, in recirculating hydroponic systems, additional formulation optimization may be beneficial to minimize the potential impact on pumps, valves, or irrigation lines.
The liquid Humikal formulation showed slight sedimentation inside the storage bottle, which improved significantly after shaking. Importantly, no visible residue accumulated inside the cultivation trays during operation.
Based on these observations, the liquid formulation currently appears easier to integrate into automated hydroponic infrastructure.
The first hydroponic evaluation of Humikal products demonstrated promising compatibility with DWC-based indoor cultivation systems.
The trial highlighted several important findings:
Although additional long-term trials and scaling studies are still required, the initial results suggest that humic acid-based Humikal technology may offer valuable opportunities not only in traditional agriculture and horticulture, but also in advanced hydroponic and controlled-environment farming systems.
