madeline is right,
flowerchild...thats assuming the weed has ZERO water content, therfore over dry (past its best)anyway.

it will keep fine for months and months in a mason jar in a cool dark cupboard, or longer in a fridge.

dont get me wrong, freezing it wont destroy it, but why bother when theres a less destructive option if its not already bone dry, just treat it like a jar of delicate spice/herbs, which is what it is.