I needed a small flower pot for my small cactus. So I made a simple pot and a matching tray. The pot has holes in the bottom so that excess water can drain off. The opening is 83mm hex.

Both things can be printed with layer heights up to 0.3mm. I recommend using at least 3 to 4 walls and 6 to 7 bottom layers to make it water tight. When printing the pot it is better to use support for the drainage on the bottom.

To give it a marble look, I used marble PLA. OK... that was obvious.

EDIT:
I uploaded a version with smaller walls. Give it a try and see what is better for you.

Disclaimer:
This work by blecheimer is licensed under CC BY-NC-SA 4.0
You are not allowed to copy this model to other 3D printing websites without my permission.