A rockery is an ornamental garden grown on rocks that have been displayed in a creative manner, usually with levels that go upward at an angle.
A rockery can be large or small, to fit your garden space. It can grow edible food provided you give the plants the soil type they need.
Growing plants in rockeries
There are many plants that can be grown in a rockery; however, it is best to choose plants that would normally be appropriate growing in a rocky environment. Alpine plants are often suited to rockeries, along with certain smaller pine trees, perennials suited to rocky soils and bulbs of many kinds.
Other types of rock gardens
There is also a term "rock garden", which can be applied to any attempt to replicate a realistic rock formation.