Impatiens growing in concrete!
Amazingly, I have impatiens growing at the foot of a brickwall where the wall meets the ashalt driveway. It looks as if they are growing in the ashalt or concrete. Needless to say, I did not plant them. They apparently self germinated from nearby plants I grew in 2005. They are some 9 inches high and are flowering well.
Have others seen this too? I don't the plants are doing any damage to the wall, right?