...you usually clone during veg, but can take clones 2-3 weeks into flower...I do...http://boards.cannabis.com/showthread.php?t=25408
some people say that you can take clones anytime...I clone on new plants as soon as they show sex...Mom's are in perpetual state of veg, so clones are available anytime...also, I have not seen any evidence of clones taking longer to root if they are farther along, I've read it; but I haven't experienced it,..