Here's the poem, courtesy of the Poetry Archives.  And all the other book anthologies I have offer the same print.  I have always seen "Gather ye rose-buds while ye may," but notice that Herrick uses both forms, ye and you, in the final stanza.
 TO THE VIRGINS, TO MAKE MUCH OF TIME
by Robert Herrick (1591-1674)
Gather ye rose-buds while ye may:
                         Old Time is still a-flying;
                         And this same flower that smiles to-day,
                         To-morrow will be dying.
                         The glorious lamp of heaven, the Sun,
                         The higher he's a-getting,
                         The sooner will his race be run,
                         And nearer he's to setting.
                         That age is best, which is the first,
                         When youth and blood are warmer;
                         But being spent, the worse, and worst
                         Times, still succeed the former.
                         --Then be not coy, but use your time,
                         And while ye may, go marry;
                         For having lost but once your prime,
                         You may for ever tarry.
AN EPITAPH UPON A VIRGIN
                         Here a solemn fast we keep,
                         While all beauty lies asleep;
                         Hush'd be all things, no noise here
                         But the toning of a tear;
                         Or a sigh of such as bring
                         Cowslips for her covering.
Robert Herrick