With benchgrafting, the critical factor is maintaining maximum pressure on the graft union to ensure a successful bond. We have found this tape to be very effective. It keeps the graft rigid. Apply Bio-Graftâ¢ tape with the adhesive side toward the plant. Approx. 50% stretch is recommended and a minimum of 4 to 5 layers must be applied to your newly grafted stock to produce good callous formation. Bio-Graftâ¢ polyethylene tape will eventually unravel itself from the graft union after sufficient callousing has occurred.