Found this on Twitter today. It's a great word for urban exploration, at least for me. I do like the plants growing in odd places: rooftops, cracked cement, and railway tracks as shown in the photograph. Sort of abandoned gardens and yet, most were never planted deliberately. Where have you seen something growing in spite of it's habitat?
Word of the day: "ruderal" - able to thrive on disturbed or broken ground, or among waste (Latin rudus, rubble). Used esp. of plant species.