Trifoliata RootStock Our Citrus trees come grafted/budded onto trifoliata rootstock, which is the standard rootstock for citrus trees in NZ with excellent hardiness to difficult soil conditions, cold soil temperature. Trees have good vigour and produce heavy crops from a young age. A trifoliata grafted citrus tree will grow naturally to 1.5-2.5m tall, but responds to pruning for height control easily.