how do I store 3 different values in one NBT tag (X, X, X)

in my mod I need to give mycelium-like blocks the X Y Z data for their seed so they can access the genetic data of their genome (how fast it should grow etc.). they pass on this XYZ data when they spread. is there a way to have them read a single NBT text tag with the data (X, Y, Z) instead of passing on 3 different NBT number tags?