This is Capparis spinosa, also known as Caper Bush, Spineless Caper, and Flinders Rose. This shrub can grow to about 3 feet tall and prefers to be planted in a spot where it can get full sun or at least partial shade. It blooms repeatedly from the beginning of Spring until early Fall. The buds and fruits of this plant are generally pickled and then used as a condiment, seasoning, or garnish in many dishes. The young shoots from this plant can be picked and cooked as a vegetable similar to asparagus. This is a larval host plant for the Giant White, Great Southern White, Checkered White, and Cabbage White butterflies. USDA Hardiness Zones 9 to 11