It's getting close to harvest time for many. I wait until most of mine have a little brown on them, and/or when they seem to fade from a glowing bright green to a dull yellow color. They should also not feel moist or cool to the touch. Anywhere in the upper half of the U.S., I think early September is probably a best bet if you're not sure when to harvest, while July and August are a little too early. Elsewhere on the globe, I'm not sure.
If drying them, use about the same weight as pellets. But since they are 80% water, if you do not dry them well then you need to use about 4.5 to 5 times as much as pellets.