Portal Seed & Elder sign Stone (Patreon)

Oh, umm... I have these two items as well which might be of interest. 

He hands you a seed that looks dead, but your parties' druid seems to think has vast potential. And a small stone. It looks like soap stone carved into a star with the ends broken off.

DM notes – if you know your Cthulhu mythos you will know what the stone is about, I would recommend printing off a few for the players. 

As for the portal seed. Get the players to spend a little time working out how to grow the seed, and then work out the destination of the portal depends on where it's grown. EG, grow it on holy land – celestial plane, in water – elemental water plane, etc.