Utrecht – In June, Luc’s garden safari moves to a roof terrace in the center of Utrecht. Perhaps not the most nature-friendly environment, you might think. Yet with many flowering plants you can simply draw nature to you. Once bumblebees have found your rooftop oasis they will keep coming back there, slugs will simply walk up even if it is 3 stories high, and butterflies can easily reach that high. And Luc is looking for butterflies – very specific ones in this case – this month.