In this review, we examine how the diverse environments in soilless horticulture can impact root exudation. Root exudation is an important process for plants; it increases nutrient acquisition, has allelopathic functions and helps creating a beneficial root-associated microbiome. In soilless horticulture, the below- and aboveground conditions vary widely in growing media, nutrient solution, light, temperature, and CO₂. These environmental conditions have the highest impact on root exudation in early growth stages. Some parameters such as temperature have been investigated, and the impact is quite clear: a higher temperature will increase root exudation rates. Many others, mostly related to the nutrient solution and growing media, are underexplored, and need more attention. Integrating findings across these factors will be essential for understanding how beneficial microbes can be optimally supported for maximal efficacy in soilless systems.

Doi: https://doi.org/10.3390/plants14030479