How to make a plant only spawn on ONE specific block

Hello, I have recently created a block similar to crimson nylium, and a plant similar to crimson roots, however in an end theme.
I want to make it so, just like crimson roots, the end root can ONLY spawn on Endcylium. I have managed to get it naturally spawning on Endcylium and End Stone, however the block can still be picked up and placed on normal stone/nettherack.
How do I make it so end root can ONLY be placed on encylium?
Thanks for the help.