The traditional countries of origin used by UK importers for the past several decades have been India and China. However, more recently these have been increasingly supplemented with supplies from Eastern Europe and the USA.
India produces walnuts exclusively in the Jammu and Kashmir region to the far north and the centre of the growing area.
Walnuts tend to be harvested in August/September by local farmers. The exporters acquire this stock through a local market system and then take the nuts to be processed. Kernels are sorted by hand into Halves and Pieces, as well as light and dark kernels, which are all packed and marketed individually.
China has various walnut crops in widely spread areas. The largest crop these days is grown in the hilly regions of the southern Yunnan province. Other crops are in Xinjiang and coastal regions. Because of variations in climate, the character of these nuts does differ from place to place, but all have been accepted by buyers. As a rule the system of harvesting and preparation is similar to India, being a traditional sort of industry, although there are some large scale factories operating at a high standard.
USA has a huge crop of walnuts in California and has become a major source of in-shell nuts for the UK and Europe. California uses mechanisation extensively in their harvesting and preparation. The US exporters offer a variety of grades which contain a mixture of broken pieces and halves, and often with light and dark kernels all together.
Recently Eastern European countries including Hungary, Romania, Bulgaria, Poland, Moldova and Ukraine has viable export crops in. Most of these origins function in a like manner to India, and use old-fashioned production methods when compared to the USA. As most of these exporters tend to ship mixed loads of Halves and Pieces, the take-up in the UK has been slower.
The absence of Chinese offers and the small crops in India these days has induced buyers to take European products, principally from Moldova and Hungary.