In order to create a natural looking rock garden, you should try to use locally available stone wherever possible. This will ensure that it will harmonise with the local landscape and it will also cost a good deal less than rock that has been transported halfway across the country. If you do not live in a stone area, you may want to consider carefully whether a rockery would in fact be suitable for your garden.
Sandstone, with its clearly visible layers or strata, is one of the most appropriate rocks for rockeries, especially if you can buy it pre-weathered. One great benefit of using rocks with stratum lines is that they may easily be split.
Tufa is a porous rock that is formed as calcium carbonate deposits around mineral springs. It is an excellent choice for the rock garden as its many air pockets make it light enough to be easily handled and transported. Its soft, porous nature also means that plants may be grown in cavities on its surface as well as in crevices between the stones.
Limestone can also be a good choice. However, never use limestone taken from the natural rock formations known as limestone pavements; so much of this stone has been taken for use in gardens that it has become an endangered ecosystem. However, limestone can be obtained from legitimate quarrying in the Pennines, Oxfordshire, the Cotswolds and Mendip Hills.
