budding amethyst recipe or method of spreading.

Possibly using something like a nether star on the amethyst block to turn it into a budding one would be too OP?
maybe it can only be spread from an existing budding amethsyt block with a nether star
similar to the nether grasses.
Or maybe a new craftable item. bonemeal + nether star + amethyst block = budding amethyst?

something similar to this. in a way thats not too OP. like very end-game way of doing.