keeping track of what, when, where

Just missed another opportunity to gather some seeds, was too late. How do you keep track of what grows where and when it is ready to gather.
My brain - too forgetful
Notebook and map - would start and lose a dozen and too cumbersome.
Handy tech gadget with built-in map and gps that you can annotate is the solutiom?

The only thing that works for me is to use little organza bags and pop them over the flower head as it starts to form the seeds, using the ribbons to tighten the bag around the stem and tie it in place. Eventually I remember to check them and I generally manage to snip the whole flower-head off and bring it indoors before the rains come. Any seeds that fall off get caught in the bag.