Oh wow! So I googled its culture but all I found was commercial culture info. I live just south of Jax? Some years we get a couple of nights of high twenties. Will they make it? Are they invasive? I noticed the plant made some runners and is traveling across the flower bed. Will I regret allowing to stay?

They disappear in the cold months and come back in the summer. Don't fuss with it and it will return every year, with some friends.

Depends on what your yard is like. Apparently they are invasive in waterways in Fl. Canals, rivers, ponds, and the like. If it is in a garden bed, it should be rather easy to control. I planted eight along my property line to make an tropical hedge with my neighbors yard. Unless it's on the edge of a pond or in a boggy spot, I wouldn't worry about it.

A.k.a. elephant ear...

http://floridata.com/Plants/Araceae/Colocasia%20esculenta/899

They spread and get larger. "Elephant ear" should give you a clue as to ultimate size. I have dozens taking over flower beds because previous owner apparently liked them.

Ship I gathered that so plan to transplant them along a fence that needs some green. They can grow there to their hearts' content.