Euonymus are a genus of evergreen and deciduous woody plants. They have a habit of producing variegated sports which are then nurtured and bulked up by the nursery trade. Some of these then named cultivars are more stable than others. In weaker strains often a vigorous green foliage shoot will appear and if not checked over several seasons dominate and dwarf out the variegated portion of the plant. This leaves, in the case of Euonymus fortune var. radicans ‘Variegatus’ a small section of the overall plant with foliage of the variegated type slowly being swamped by glossy green evergreen foliage.  Where the plant is mature and at an advanced stage of life the best option is to propagate vegetatively from the variegated shoot and either embark on a radicle prune or grub out and use the opportunity to replant.

Euonymus fortunei var. radicans 'Variegata'

Euonymus fortunei var. radicans ‘Variegata’