Metropol

i want to play a practical joke on a friend by making one of their plants in their office go a bit smelly. i wish to empty some sort of liquid into the compost of the pot, i am just wondering if any of you have any suggesions as to what i could use to make the room really really stinky after a couple of days?

Wee?
or
Let some milk go off then pour that in?


Both if which may kill the poor plant.

I was going to say urine

Howver another suggestion could be take a tin of sardines (or another smelly fish) & pour out the brine into the compost. He will never know until he smells it.

It's probably not going to do his plant any good, and doesn't sound terribly festive to me...