Many years ago I grew my runner beans up a wigwam, and being a bit short of dalek space at the time I just dumped all my garden waste on top of where they'd been growing that summer.
When I got round to shifting it the following spring I was surprised to find lots of new bean shoots, mostly at least 2 or 3 from each original plant. Only reasons I didn't continue with the experiment was that I'd planned to grow them in rows that year, and also with my light soil I wanted to get plenty of organic material underneath the next crop.
Having once been very nearly caught out by a late frost in early June, I never plan to plant mine outside until then, which means sowing indoors in early May, although I do sow some directly as well to extend the cropping season.