'Rochester' is the incredible single yet multi-petalled white lilac, a seedling of 'Edith Cavell', selected by Alvan Grant and Bernard Harkness at Rochester's Highland Botanical Park.  This is very rare and not easy to propagate.  It's slow growing and will be on the small side.  Mid-season.  Grant 1971.  Grows 6' H x 4-6' W. Syringa vulgaris 'Rochester'.