Hmmmm...how can I describe the size. I'm terrible with measurements. (Although I can pick the EXACT size container you will need for your leftovers - that's my super power!)
I know! I'll find a picture -
OK so the black one at the left is one of those standard plastic lily and lotus pots you can buy at pond stores. It's maybe 18 inches across the top. That one was new last year - beautiful pink and yellow flowers. That one stayed right there all summer. Not the prettiest pot, but the plant was so lovely you really didn't notice!
The other two beige colored ones are about 16 inches across - those are the two that went into the pond. We overwintered those two in the house the first two years. We were waiting for them to get a bit larger as the koi do find lotus root to be very yummy! Once they get aerial leaves they don't bother them anymore for some reason. And you can't see pot number 4 - it's behind that big blue pot in the front. That had a teacup lotus which was also really pretty snow white.
We had a 5th one that never bloomed and ironically was the only one that my daughter bought already potted and growing...and paid about $70 for - she was rather disappointed about that one needless to say. Hopefully it will come back this year and flower for us. All of these are overwintering in the pond this year - we tried it for the first time last year and they all came back, so we won't bother bringing them inside again.
The big blue pot in the front did have lotuses the two years prior, but it got to be too big of a pain to get them out in the fall so we stopped using it for a lotus pot. It was GORGEOUS when it bloomed! That was our first lotus attempt and it was addicting!