This is an adjustable support for bamboo sticks or orchid rods done in Open SCAD.
You can use the thingiverse customizer in order to adjust for the diameter of the support that you need and also for your own sticks/orchid rods.
I have added an example .stl for a support diameter of 140mm and bamboo stick diameter of 5mm .
Top/Bottom Layers: 3
Wall Thickness: 0.8