harvest time?

When the hairs turn orange the ovula, which is where the hairs come from( and also where the seed would go if it were pollinated) starts to swell making the bud thick, when you first see hairs let them die(orange) and let it happen again to the new hairy growth( hence second turning) , let that go aroange and the trichromes should be everywhere by then(week 8) all those trichromes on the hairs and leaves and the ovula start to get large,...

wait for 7-10 weeks minimum

I agree with DEL. My plant's hairs (pistils) were 70-90% amber after only 3 weeks flowering. Surely the plant was not done growing then.

The most accurate way to tell is by looking at the trichomes under a microscope. When a few of them turn amber from THC degradation, then its time to roll.

P.S. I believe my pistils turned amber so early from a pH problem.

they will turn if the light burns them

even the bottom ones turned. If it wasn't pH, it was because miracle grow soil caused over fert.

So mountainman,

You now that know you will need at least another six to eight weeks of flowering before harvest. There are a few other thing to consider. Potency will be determine by the genes you have selected to grow nothing can increase or decrease this item. What you should be considering is how to maximize the yield at your harvest date with that 400 watts. How you ask? Well, there are factors that you as the grower can address or ignore. They include pot size, available fresh air, amount of fertilizer and the amount of additional CO2 added. I will now leave you to ponder each of these issues on your own. Each one of them make up a small part of the overall picture yet each one equally important in maximizing the yield. Happy growing.

Loco