Sors

I'm not completely sure about coral. BUT, I do have a friend who's growing a shrub out of a long horn skull. Since both bone and coral are mainly made up out of calcium, I'm thinking the calcium probably stays in and doesn't leech out. She'd been fairly successful with it as well, I'm thinking this is the second year she'd had it.

Either way you should give it a shot and report back eventually.

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