Klasmann-Deilmann, a leading international substrate provider, recently conducted a Research and Development (R&D) trial in Geeste, Germany, to evaluate the performance of its “TerraCoal” biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More in the cultivation of Dieffenbachia and Calathea. The study focused on how moderate biochar inclusion affects plant quality, pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More stability, and overall cultivation performance in peat-reduced and peat-free growing media. Results indicated that a 10% biochar concentration supported stable root development and consistent growth across both species. This trial represents a significant step in validating biochar as a functional component in professional horticultural substrates aimed at reducing reliance on peat.

The primary challenge addressed by this trial is the inherent difficulty of maintaining crop quality and physiological stability when transitioning away from peat-based substrates. Peat-free and peat-reduced mixes often exhibit less predictable pH behavior and require more intensive irrigation and nutrient management, which can lead to uneven plant development. Calathea, in particular, is highly sensitive to fluctuations in substrate conditions and pH shifts. Without effective buffering agents or structural stabilizers, growers face increased risks of nutrient uptake issues and reduced marketable quality in high-value foliage crops.

To mitigate these cultivation risks, Klasmann-Deilmann integrated 10% TerraCoal biochar into the substrate recipes. The solution leveraged the physical and chemical properties of biochar to enhance the buffering capacity of the growing media, particularly in peat-free formulations. During the trial, the biochar-enriched substrates maintained more stable pH values compared to the control groups. This stability proved critical for the Calathea rufibarba, which produced superior leaf substance and color. The inclusion of biochar also provided a more forgiving environment for irrigation management, assisting growers in navigating the technical complexities of alternative media.

The outcomes of the trial confirm that biochar can effectively offset the technical drawbacks of peat alternatives while significantly reducing the carbon footprint of the horticultural industry. In addition to achieving uniform root systems and stable growth, the use of TerraCoal allowed for the partial or full sequestration of the CO₂ emissions associated with the substrate’s production. For Dieffenbachia ‘Camilla’, growth remained consistent with traditional standards. These findings suggest that 10% biochar inclusion is an optimal threshold for enhancing substrate performance and environmental sustainability in professional greenhouse operations.