The Trifoliate Orange (Poncirus trifoliata) has been grown in China for thousands of years and is the preferred rootstock for heavy soils.

Trifoliate has a tolerance to environmental and soil conditions Poncirus trifoliata is most suitable for lime-free soils and can withstand cold and wet conditions. However, impeded drainage can result in ‘Sudden death’ of trees on this stock.

Trees on P. trifoliata grow well on fertile clays to loams but are intolerant of highly acid or highly alkaline soils. They also react to saline conditions, Poncirus trifoliata is highly resistant to Phytophthora root and collar rots caused by the fungus Phytophthora citrophthora and to the citrus nematode (Tylenchulus semipenetrans). It is immune to citrus tristeza virus.

This rootstock is responsive to viroid dwarfing and is recommended as a stock for viroid dwarfing of oranges.

Poncirus trifoliata is generally a good rootstock for oranges. most mandarins and lemons with the exception of Eureka lemon. A major drawback in the use of P. trifoliata is the slow initial establishment of new plantings. Cropping efficiency is good. Trees propagated on P. trifoliata are suitable for planting at high density. Field performance in tropical and sub-tropical regions is generally poor.