Hi Mary,
Usually I use a 30-50mL (1-2 oz) dark amber bottle, but sometimes people use even smaller bottles. Often I find that the mother essence would make far too much flower essence for me to ever bottle so, I return most of this back to the earth once I have made the stick bottle. For the stock bottle, I often also use 30-50mL bottles for. It mostly depends on how much flower essence you want to make and how long it will last for.
Warmly,
Benna