@Nagassh I don't think it comes from WQ's, just emissary caches.
The majority of the berries gotten in my guild has been from mythic+ dungeons, which is why we've spammed them so much. I dunno what "plenty" means for you, but there's people in my guild with 500+ and growing run. I'm way too casual for that, so I'm closer to 300ish iirc.