The best size for any Mini OR Mini-Fl's is a 7 gallon pot that is the best i grow my minis and mini-fl's in half wine barrels but that is what i like them in but a 7 gallon pot is the best good luck

Hi John,
If you live in the southern States 7 gall. pots are OK, but up north, Midwest, you can use 2 & 3 gall. pots. I live on Canada's west coast.
I have most of my minis in 2 gall. pots and only a few in 3 gall. Mini-Floras I put into 3 and 5 gall. pots.
Many minis I leave in 2 gall. pots for 2 to 3 years and then repot them or put into 3 gall. pots.
One more note :
If you buy new minis in 3" pots you can first put them into 1 gall. They always take off faster in smaller pots. A few month later when the roots fill the 1 gall. pot then you can repot into bigger onces. Also, if roots go around in circles at the bottom I take a large steak knive and cut about 1/2" off right across the the bottom. This way, new fine hair roots will develop faster.
Good luck George Mander

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I live in Illinois in the central part. When I dig up a ground grown mini, it has a huge root system. I've seen roots over 3' long. I grow minis in pots along my drive so the mape tree roots don't get them. I use 7-10 gal size and one to a pot. Unless it is a small type mini, then a 5 gal will do. But a Jean Kenneally would need a big pot. Mine get 4'tall or more. My minis are doing great!,by the way I sink the pots into the soil. No winter problems, and in the ground they don't dryout so bad.

What about the plants that are only supposed to get to 12" - 18" high? I was hoping I could grow some in smaller pots. Thanks!