"Steve" wrote in message wrote

While we're on the subject of Scarlet Runner Beans...
(snip)
I'm writing because I read that these runner beans actually produce a
tuber and would be perennial where the ground doesn't freeze. I believe
I read that these tubers could be saved and replanted in the spring to
produce a faster growing plant next year compared to starting over from
seed.

They are also called Seven Year Beans. They are perennial but I don't know
if from a tuber or not and I wouldn't dig one up as they are simply left in
the same place and come up again the next year. As you say, this applies to
where the ground doesn't freeze, but they are also a better cold climate
bean than the French Bush bean.