You will know when...trust me....

The last week or even the last few days, the clear trcihs will show the THC bursting thrugh the membranes and filling the trich heads with white color. Almost a pure white cloud look.

The clear trichs arent yet filled with the most THC. Once the plant has produced enuff, the membranes will split and the THC will flood the mushroom head.

It will become stark white and I would want to wait until all of them or most all of them are at least white.

Just my preferences.