In soilless growing methods it can be often (not always) observed that the roots ‘are kept in the dark’. What is the reason for it? Is there a general answer or does it also depend on the specific plant-species?
Depending on the length of time you are growing the plants for, you might get algae, bacteria or fungi growing on the roots or on the inside of the containers. This may have consequences for nutrient acquisition through competition between the plant and the other species.