Light does not have any effect on plant roots and is required by plants to create food that will produce healthy growth for both the plant and the roots. Roots can become green as a result of algae growth on the surface as a result of overexposure to light. Algae growth can be reduced by shading the roots.

Does sunlight help root growth?

Plants seem to pipe sunlight directly down into underground roots to help them grow. Light receptors in stems, leaves and flowers have long been known to regulate plant growth. Roots also have these receptors, but it has been unclear how they sense light deep in dark soil.

Is sunlight bad for roots?

Soil Roots and Darkness

In the same way that upper growth on plants bends toward well-lit windows, roots naturally grow away from light. They seek darkness and protective moisture instead. In transparent pots, these roots avoid light-penetrated areas of soil. ... When light dries soil out, tender root tips can suffer.