Orlaya grandiflora

Orlaya grandiflora, the white laceflower, is a species of flowering plant in the family Apiaceae, native to Mediterranean Europe. Growing to 90 cm (35 in), this is a multi-branched annual with divided ferny leaves, and flattish panicles of pure white flowers over a long period in summer. The uneven size of the individual florets gives it the appearance of lace, especially when planted in large swathes. It is a recipient of the Royal Horticultural Society's Award of Garden Merit. It prefers a sunny, well-drained position....read more on Wikipedia.