You can find old walls like this in French and Italian villages, especially -but not exclusively- in Provence and Tuscany. They are works of art in themselves, painted by time, the climate and the patient hands of generations of men who colour-washed the walls of their houses, layer over layer over layer.
I tried to reproduce my impression of such a wall, creating one that never existed. A simple gradient to begin with. Then:
The texture applied to the wall gradient is from lunartex www.lunartex.deviantart.com I really love her textures!
Some additional coloured stains using kuschelirmel's www.kuschelirmel.deviantart.com Splat brushes.
The window pane is from my own stock.
The golden pear is from Enchantedgal-Stock www.enchantedgal-stock.deviantart.com
The texture applied to the inside wall is from sundel www.sundel.deviantart.com
The ivy brushes are from ro-stock www.ro-stock.deviantart.com