tha dank

What part of the plant do I check to find out when to harvest for trichomes this is my first grow and appreciate the tips and also why do my lower buds look ready and my top buds look like they still need for time is that normal I will put pics below thank you 2 pics of the one where the...

Has anyone tried these and had a good outcome. i see that noone stocks them anymore and was wanting to see if there worth working on, acquire'd a pack last spring or so and increased the packs population. Just want., others trials and tribulations on the genetics.