Leave a building untended for a few years and it's almost guaranteed you'll get this plant growing in the cracks, crevices, gutters and chimneys. This one was ten or so feet up and appeared to be growing straight out of the wall. Now not everyone likes these plants and some go so far as to call them weeds which is just impolite in my opinion. Personally I like them so much I've got four or five of them flowering away in my garden all covered in dozens of butterflies, moths and bees. They almost make Summer tolerable.