Cosmos - will they self seed?

[bario1]

Hi,

If I chop down my finished cosmos and leave them where they are, will they come back next year?

Cheers.

[roitelet]

They are annual so the plant will die, they may self seed although mine never have. I save some of the seed and start again the following year.

[hamamelis]

I had a few self seeded last year. They didn't get going until surprisingly late in the season though, well behind the ones I'd sown at home (appeared late May, if I remember right). Dunno why.