I live in the Arizona desert and have some grapevines that came with my house. After 10 years of dodgy production and greedy ground squirrels, my vines are relatively full of grapes.
Based on their appearances, and the fact that they're surviving here, I believe they are Thompson seedless grapes. Right now, they are fairly small and a little less sweet than I would like. They haven't grown that much bigger recently so I'm wondering if they're ready to pick. Knowing that as the summer goes on, the wildlife will eventually get to them and the sun will burn the leaves, I'm wondering if this is the best they can do or if I should hold off a little longer.
What are good signs that grapes have reached peak ripeness and are ready to harvest?