This is a fun and cute brontosaurus vase. This girl looks amazing with any kind of flower you like.
If it's important to you that this is water-tight, I can't guarantee that it will be. However, to have the best chance I would: A) do not scale down B) Print as solid as possible (>=3 outer walls, >=99% infill, >= 2.4mm bottom layer height) C) Ensure that your printer is not under extruding.
Good luck and have fun!