Flower growing from wall

Flower growing from wall

Observation - Flower growing from wall. Description: Is this Red Valerian? My book says it is an introduced species, often found growing on dry banks, walls and cliffs and is more common in the south, getting less and less further north.

Is this Red Valerian? My book says it is an introduced species, often found growing on dry banks, walls and cliffs and is more common in the south, getting less and less further north.