Photos of the Poncirus trifoliata at Surrey University, Guildford, Surrey, England. Taken with flowers fully open, 17th May 2001. This fine plant, about 2.5 metres tall and wide, was one of two grown from seed about 20 years ago.The second plant was apparently removed after inebriated undergraduates complained of being speared by its large thorns! This is a large-flowered variety with flowers about 7cms in diameter. Click here for location details of this and other Poncirus trifoliata plants.