How long does your hair have to be to bun?

I see lots of comments and style where you lovely ladies bun your hair. My hair when twisted comes to the nape of my neck. if I pull a twist and stretch it out it is at my collar bone. I should measure in inches, but.... Anyway, I.can.not.get.a.bun! I thought my hair was long enough, but I really just get a really thick puff. What am I doing wrong? I really want to do some protective styling for the winter. So if you can do a bun, how long is your hair?

I just found a ruler and measured my twist, in the back I get 8-9" and top or sides I get 11". I think I have this weird in-between length. Would love to get some feedback, thanks ladies!

I can bun! I have about 9 1/2 inches in the front and sides, 8 inches in the back, and about 13 inches in my crown. The challenge for me is getting the back (which is the shortest) in the bun without it frizzing and coming out. I find that if I either bun on soaking wet hair (hair's more elastic then) or bun on really stretched hair after a braid out I'm usually good.

HTH!

I wonder how my hair will bun now?? I got quite a bit trimmed off before putting in a sew-in.. after i take it out maybe I'll measure before struggling to bun.. I think it may be too short.