Alchemilla mollis on a patio

Alchemilla mollis

What I like about this patio (apart from the amazing view over Bath) is that it Alchemilla mollis all over it. The only self-seeders I get on my patio is weeds, so I’m intrigued as to how this got here – was it planted, or did it come naturally? It reminds me of the fab patio area at Gravetye.