You might have to scrape it off of the rock. My GSPs won't "peel" off of a rough surface like Tonga rock, and I have to scrape it off with a small plastic kitchen scraper. If you're able to peel or cut yours as Pennies suggested and want to frag the cuttings, just glue them onto LR rubble using super glue, then give them a week or two to firmly grow onto the rock. They're good trade items that way.