They have two work tables. It goes quicker if you work in pairs, with one person gathering and cutting clumps of greens and fanning them a bit and the other person placing them in the form and crimping the wire.
Thus is a closeup of the wire frame and if you look closely you can see how it is set in the crimping tool.
When you have a clump of greens laid the way you want them you step on the floor pedal to crimp the wire.
A few decorative touches and voila!
They had this wreath hanging in the shop. (The flash really messed up the colors.) It was done with hens and chicks or some type of sempervivum. It would never have occurred to me to make this type of wreath and I have no idea how it was assembled but it was much prettier than the picture.