Rock gardens begin by selecting the area of your landscape where this kind of garden will be ornamental, easily seen and work in with the flow of the rest of the garden. You can build a whole landscape out of the rock garden style, making some areas bolder by using larger rocks and higher profile plants. Or give a rock garden a special place of its own near seating where its details can be appreciated.
A rock garden should start with good drainage. You can have a raised garden or a flat one, but always make sure there is a lot of good, open material beneath so the water passes through the soil quickly. Most plants that work well in a rock garden cannot stand stagnant water around their feet.
You also want to choose good looking rocks to build your garden. You can use all the same color or type of stone, but do vary sizes and shapes. Too many kinds or colors of stone will look disorganized. Stones all the same size and shape will appear boring. Select a nice assortment of related-type stones and scatter them somewhat at random as nature would.
Select plants that look good in rock gardens. There is a huge list of great plants to use for a rock garden. Again, go for diversity. Tuft some taller plants near bigger rocks, spill creepers over edges and mound piles of foliage in groups. Slot in a few bulbs to send their leaves shooting through the foliage of lower plants and end in a fireworks display of brightly colored flowers.
Other ways to build your rock garden to make it more decorative is to add a small dry riverbed that snakes around to the bottom and also conducts away extra water when it rains hard. Or if you are into statuary, you can find a piece to decorate your rock garden, nestling it in with the rocks for subtlety. Look at other rock gardens and photographs to stimulate your creativity. This is one type of garden that is limited only by your imagination!