I wouldnt put jugs or anything like that out there, it's just more stuff for hikers/helicopters ect to see and then they know someones probably growing around there. plus im pretty sure the amount of rain collected in the bucket will evaporate in equal time, meaning it will rain- evaporate, rain - evaporate, it wont compound each time it rains.
unless you engineer some sort of contraption to work efficiently it a waste of time, someone posted somethin about these things called "tree rings" or somethin like that, they look good but you gotta fill em up yourself.