Hyacinth used to be a boy's name (as in Laennec, inventor of the stethoscope), but that might be a tad difficult to live with. Also Narcissus.
I always thought Tarragon would make a good boy's name....
More sensibly: Rowan, Joshua (as in the tree), Woody, Dale, Dean, Storm, Eden, Ashley, Sandy, Ray, Ambrose, Merlin, Bailey, Basil, Cosmo, Griffin, Forrest, Jacenty, Roscoe, Tor, Jasper, Leo, Lyndon, Peregrine, Reynard, Robin, Sylvester, Willoughby, Wulfric?
Or change theme and try Sextus or Sixtus?