It's good for the flowers...

What's the proper protocol when you catch someone having a whizz in your garden? My landlord was doing some work on the upstairs flat and there was someone, either a elderly handyman or his dad that was around as well. In the early afternoon this old guy walked into my backgarden, apparently not noticing that I was watching him. Just as I was about to go and challenge him, I noticed he was peeing in the rose bush. He was standing under my washing up on the line, apparently oblivious to the noise from my TV and having a slash in my garden. I did what any English person would do, I immediately left the room and waited until he left before coming back out. I mean, what can you do, except hope that you induce a cardiac arrest on the incontinent old fogey when you shout "What are you doing to the azalleas?!" It's not really something you can bring up afterwards, "Oh yeah, I heard you were drilling and, oh yes, your Dad came and spent a penny in the back garden".