This modern minimalist planter fits either a small plastic pot (see dimensions) or can be used directly to plant in.

Print without support and reduce infill to 10% adaptive cubic. For additional water tightness, set the wall count to three. If needed, there is an optional instance in the files featuring a negative volume to create a drain hole in the bottom of the planter. The drain is disabled for the version compatible with the plastic pot and enabled for the version that is meant to be filled directly with soil.

I used eSUN eMarble filament for a very nice print result, but different materials obviously work too. Keep in mind, that you'll see the layer lines with less textured filaments.

The small plastic pot used in the pictures has an upper diameter of 90 mm, a 2 mm high, 3 mm wide rim and is 70 mm tall with a lower diameter of 65 mm.

File created in Fusion 360. If there is enough interest, I might make a tutorial on how to achieve the low poly look.