Wheat is generally produced in temperate countries and there is only one harvest each year. The majority is produced in the Northern hemisphere, and harvested in the period June to September. Southern hemisphere crops are generally harvested in the period between November and January.
During the early years of the 21st century, global demand for wheat exceeded supply meaning that there was a steady draw-down in stocks. This led to a sharp price spike in 2007, which encouraged a strong supply response leading to record global crop levels in subsequent years.
UK-grown wheat usually accounts for 80-85% of total usage by UK millers. Different wheat varieties have different qualities, meaning that some are better suited to some types of flour than others. Millers classify wheat into four groups; Group 1 for varieties best suited to breadmaking, Group 2 for varieties suited to breadmaking but may not suit all millers all of the time, Group 3 for varieties are best suited to cake and biscuit manufacture and Group 4 for a range of other purposes. The availability of wheat from different groups is therefore important to millers in planning their purchasing for the year. More details about individual varieties can be found in the nabim wheat guide, to be found in the Wheat Varieties section of this site.