The genus Arenaria, known also as Irish Moss, or less attractively Sandwort, consists of plants that are usually mats or tight cushions of tiny leaves, with short-stemmed starry flowers, usually white. They make excellent rock garden plants.

Arenaria montana 'Snow White' is the mountain sandwort, a ground hugging alpine which creates a low evergreen cushion of grey-green leaves, and bears masses of snow white slightly trumpet shaped flowers.