well if u have yellowin leaves, peein on ur plants might help. even though, this is HIGHLY not recommend for a number of reasons. human pee is not harmful for the first 3 hours its out of our bodies. pee is high in nitrogen (hence its good for yellowing leaves) it also has trace elements. pee also (over time) will turn 2 amounia (spelled wrong) either way. prolonged use will poisen ur plants.
it is NOT recommended , but u could add it every week if u needed 2 help with yellowing leaves.