google "Kings Mums". THey have several different green button poms. I have bought chrysanthmums from them twice and now have 6 of them blooming in my greenhouse over winter!
I would not risk them outside in my zone over winter, but they summer in the garden just fine. In the fall, take cuttings and start them over in smaller pots inside. They will be ready to plant out again the next spring. Mine need to come in side before they bloom so having them in big pots helps.

Thank you, Liza.
Your experience is very helpful. So I can grow them just like other mums. I know Kings mum. But I am wondering if I can just buy a few cut flowers from floral store and propagate by cuttings.

I think they use an inhibitor of some kind. I tried this myself and the flowers just turned brown and dried up without rooting.