When do I Harvest?

[Shovelhead]

Got a couple plants....one is a Big Bud, the other ...unknown, just killer stuff.
The unknown has been goin since March...Skunky as can be...but still is (very slowly) gettin larger (buds) The Big Bud is bending over from the weight but still too young...Need some help on the harvesting time.

I got Pix

[cannabis2]

give them some support for the buds use sticks to prop them up harvest when one third of the hairs are amber