August to October, depending on the latitude, altitude, and climate. Where frost does not occur fruiting is continuous and plants do not lose their leaves. Occurrence and cultivation China Lycium barbarum has been cultivated in China, along the fertile aggradational floodplains of the Yellow River, for more than 600 years. It is still extensively cultivated in the Ningxia Hui Autonomous Region of north-central China, centered in Zhongning County, totaling 200,000 acres as of 2005, The region produced 13,000 tons of fruit in 2001, accounting for 42% of the nation's total production of goji berries. The plant is also cultivated in the Xinjiang Uyghur Autonomous Region of western China, The berries of L. barbarum are the only therapeutic grade ("superior-grade") kinds of wolfberries used by practitioners of traditional Chinese medicine. As Ningxia's borders merge with three deserts, L. barbarum is also planted to control erosion and reclaim irrigable soils from desertification. United Kingdom Lycium barbarum has been used since the 18th century in the United Kingdom for hedging, especially in coastal districts. Its red berries are attractive to a wide variety of British birds. The plant continues to grow wild in UK hedgerows. On 15 January 2003, the Department for Environment, Food and Rural Affairs launched a project to improve the regulations protecting traditional countryside hedgerows, and specifically mentioned Duke of Argyll's Tea Tree as one of the species to be found growing in hedges located in Suffolk Sandlings, Hadleigh, Bawdsey, near Ipswich, and Walberswick. Importation of mature Lycium barbarum plants into the United Kingdom from most countries outside Europe is illegal, due to the possibility they could be vectors of diseases attacking Solanaceae crops, such as potato or tomato. Australia Lycium barbarum introduced to Australia became naturalised in south-eastern coastal and sub-coastal regions, and is regarded as an environmental weed in the provinces of Victoria and Tasmania. It is often found growing in disturbed sites, native bushland, and riverbanks, often forming dense thickets along the latter. It overlaps and is often confused with Lycium ferocissimum, a similar species originating from Africa. Chemistry Phytochemicals present in the fruit, root, and other parts of the plants have been studied in some detail. The main compounds in the fruit (23% of the dry mass) are polysaccharides and proteoglycans. Carotenoid pigments are the second major group, chiefly zeaxanthin dipalmitate. Other detected compounds include flavonoids derived from myricetin, quercetin, and kaempferol; hexadecanoic acid, linoleic acid,