I have several cascade plants with lots of hops. The tips are browning a bit and they smell great. Is there any harm leaving them longer? Can you leave them on too long?
when you suspect they're close to being ripe, grab a few cones on a daily basis and do the 'rub-n-sniff' test. you'll notice the aroma increase up to a certain point. then things start going down hill. i don't know if it's oxidation of the oils or what, but at that point, they seem to be just beyond the peak of perfection.