Fruit trees with more than one variety growing on the tree are called ‘doubles’, ‘triples’, ‘family trees’ and ‘fruit salad trees’. Compatible varieties are selected to grow on the one tree which must be in the same family. It is not possible to grow a tree with apples, pears and plums on it. However it is possible to grow a tree with a peach and nectarine on it, as these are both in the Prunus family so are compatible.
Waimea Nurseries grows a range of fruit trees with two or three varieties on the one tree. Some fruit types are grown with both varieties grafted at the bottom of the tree trunk, while others are grown as tiers of branching. The method of propagation is based on the natural habit of the fruit types, to ensure a good shaped tree will result. The tree should be labelled with a small mark of paint to identify which part of the tree each variety is located. This also helps to avoid the potential of accidently pruning off one of the varieties.