Arabis Snowcap.

Arabis alpina is a dwarf, compact growing plant that forms a mounding cushion of olive-green leaves and blooms with dense masses of flowers. ‘Snow Cap' is a large white-flowered cultivar, the flowers almost completely cover the foliage throughout spring.
Arabis is a very popular and useful plant and one of the best for the rockery. It is related to Aubrieta and is used in a similar fashion. It makes a good groundcover, can be used in borders and is excellent for trailing over the edges of containers, over stones or down walls.

Its attractive evergreen leaves forming a low cushion about 15cm (6in) in height. In mild winters the leaves hold their looks deep into winter. It is tough & hardy, simply provide ordinary good soil and excellent drainage.
Always one of the earliest spring flowers to appear, 'Snowcap' looks wonderful in spring containers. Plant under spring-blooming bulbs with Narcissus, Primula veris or Viola the pretty white blossoms will fill the void when yearning for blooms is tugging at your core.