What is air pruning, and why is a breathable fabric better for roots?

Air pruning occurs when roots reach the breathable bag wall and meet air; the root tip dehydrates and stops, prompting the plant to grow more fibrous feeder roots inside the bag instead of circling into a root-bound mass like in plastic pots. The result is denser roots, better uptake, shorter transplant shock, and higher survival. HOKBG woven fabric is breathable and permeable by design for exactly this mechanism.