This plant does, as its name suggest, grow out of walls - particularly limestone walls. The yellow composite flowers are quite small but usually there are many of them in one flowerhead. The leaves which can be seen in the LHS photo are a little like Taraxacum sp (Dandelion) or perhaps Sonchus sp (Sow thistle) leaves. It has an odd distribution being uncommon on the Cornish peninsula with patches of scarcity around Lincolnshire. It is common in the rest of England and Wales but in Scotland is mostly found in the west. In Ireland it is dotted about but common in the limestone areas of the west.

LHS: Great Orme 18th July 2002 RHS: Banks of River Tyne 3rd July 2005

Added on December 20th 2005, updated 28th January 2021 2011