This was modeled in Autodesk Fusion 360. My wife wanted a pot for her orchids with good ventilation, so I put this together.

I printed several of these in PLA, using supports just for the flat area going around the outer portion of the base. The center portion of the base, which is cone-shaped, prints fine without supports.

In your slicer software, just set the support overhang angle to something very high (like 80 degrees), and it should generate supports just for those flat parts of the base.