I knew what you meant Annie
You could also use marbles or rocks to hold it in place.
The dowel doesn't need to be that long, just long enough to stick out of hte pot, and a little ways into the felt tree. The following is how I would do it:
paint pots
cut 2 triangles out of desired felt color
sew or glue on buttons and bows
place felt together, outsides facing in, sew together (or if gluing, then just glue together, right sides out)
after sewing, turn insides out, so right sides are outside
stuff with batting or whatever you have on hand (if you use glue, let the glue dry completely)
shove stick into tree
stick into pot
done