There are three ways to acquire a citrus tree for your home garden.
The easiest and most reliable way used by most home gardeners to start is by buying a young citrus tree from a reputable nursery or tree care specialist. Almost invariably the young tree sold will be a combination of two trees: one variety of orange, for example, grafted onto to rootstock of another. The mature tree of this kind of graft will be the variety of the scion, not the variety of the rootstock onto which the scion has been grafted. If this all seems like a complicated way to grow a tree, it is. But grafting has two advantages. First, it can extend the range and hardiness of the scion variety because the scion can 'piggyback' on the qualities of a more durable rootstock. Secondly, grafting permits the grower to more precisely control the characteristics of the mature tree. Left to her own devices, Mother Nature can be difficult to tame and may try to wander off and start a new variety.
However, for the more adventurous tree grower, it is certainly possible to start your own citrus tree either by
growing from seed or by
doing your own graft.