Been flowering for months and still going strong.
No interactions present.
It's definitely Mallow, and clearly not common Mallow, Malva sylvestris, as the leaves are the wrong shape. (they would be more palmate.)
I would have said "garden escape" , and would have chickened out of trying to ID to species, but I am perfectly happy to accept Stewart's ID!
How to take close-ups with cheap phone and hand-lens:
Field Guides for Budding Botanists:
Lat/Lng: 50.3417, -3.5763
OS grid ref: SX879502
In the garden but right on the edge of town and woodland.