Lysimachia nummularia "Goldilocks" also known as Creeping Jenny. This is a perennial ground cover that is lime green in colour and has little yellow flowers. Can be used in the garden 

Flower: Small yellow

Growing Habit: Ground cover

Uses: Walkways, borders, ground cover, containers, 

Height: 1"

Width: 12"-24"

Light: Full sun, part sun, can take shade but will turn green

Soil Type: Humus - rich, clay, loamy. Can tolerate moist as well as well drained

Soil Ph: Acidic, alkaline and neutral

Pruning: none

Zone: 3-10