I'd like to preserve a master Claviceps Paspali culture indefinitely. What would be the best method?

I am thinking of buying a freeze dryer and using that. But I'm unware of the exact settings , method, and technique (i.e. temperature, time to freeze, etc).
Once preserved using the freeze drying method, at what temeperature should it be stored?

All comments are welcome and appreciated.

Excellent, thank you! Much appreciated!