So, instead of extruding a lot of tiangles I duplicated and separated a circle from the top.
Then I filled it with a NGon face and moved it to the bottom of the hole.
After scaling to 97% I extruded it upwards and checked the render.
I didn’t like the topof the stem so I beveled the top edge-loop (CTRL-B)
… oh, and as you can see I oiled the stem ever so slightly to make sure it didn’t get stuck…
