Rust is not good but i have pierced many stems. I supercropped my plants to keeep them short and a single cola. I would put almost 1 inch growrocks in some of the lower stalks after gauging up. The stem on each side of the rock was the size of my pinky on a 13 inch high finished plant. I believe India was the place where the style of growing originated,but it could have been the Indians. The native americans would also grow in mounds to give the plants more oxygen to the roots. The peircing takes practise and my advice is keep your cracks clean and green. I had hundreds of plants to practice on and have only done it on super cropped plants.

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