A white-flowered ornamental garlic with stems that are circular in cross section, and with hairy edges to leaves

Allium neopolitanum has similar flowers, but stems trianguar in cross-section.  Several other garden escapes may be present - refer to keys in Stace 4th edition (2019)

Detailed photographs of stems and leaves as well as flowers needed

a non-native species from the Mediterranean region - an occasionally naturalised garden escape