This grower is fairly sure of this plant identification.
Saponaria officinalis (Soapwort). This plant produces quite large pink flowers. The leaves are oval smooth and mid-green. This plant is often found in the wild in Northern Europe.
They will produce fully to frost-hardy plants which need sun and well-drained soil.
Walls, rock garden, waste ground.
Italics = data drawn from parent genus or speciesView Full Plant Finder Record