Matthew married his maternal first cousin, Christian Nicol in 1817, and they had eight children: John (born 1818), Robert (1820), Alexander (1821), Charles (1824), Euphemia (1826), Agnes (1828), James Edward (1830), and Helen Amelia (1833). Robert farmed Gourdiehill in Patrick's old age, Alexander took over the German interests; the other three sons emigrated, initially to America. Matthew became interested in the colonisation of New Zealand and was instrumental in setting up a "Scottish New Zealand Land Company". At his urging, James and Charles Matthew emigrated to New Zealand, where they set up one of the earliest commercial orchards in Australasia using seed and seedlings from Gourdiehill. John Matthew remained in America, sending botanical tree specimens back to his father; these included (in 1853) the first seedlings known to have been planted in Europe of both the Giant Redwood ("Sequoiadendron giganteum") and the Coastal Redwood ("Sequoia sempervirens"). A group of trees of these species still thriving near Inchture in Perthshire comes from these seedlings. Matthew gave many more seedlings to friends, relatives and neighbours, and redwoods can be found throughout the Carse of Gowrie; these as well as some elsewhere in Scotland (e.g. at Gillies Hill near Stirling Castle) are thought to have been grown from the 1853 seedlings. His reputation as a local celebrity faded in the twentieth century, when he was remembered as a "character" who at the end of his life became convinced that "someone very dear to his heart" had become a bird, and therefore forbad his garden staff from controlling the blackbirds that were destroying the fruit.