Barley (Hordeum vulgare L.), a member of the Poaceae or Gramineae, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 15,000 years ago. Barley ranks fourth in importance among cereals, behind wheat, maize and rice. Spikelets are arranged in triplets which alternate along the rachis: six row barley (Hordeum hexastichum) can produce 25-60 grains, while two-row barley (Hordeum distichum) produces 25-30 grains. Four-row barley is a loose six-row barley.
Wild barley is two-row, and most cultivated barley is of the six-row type. Barley has been used as animal fodder, as a source of fermentable material for beer and certain distilled beverages, and as a component of various health foods. Barley grains are commonly made into malt in a traditional and ancient method of preparation.
Soil: Barley grows well on well drained loamy or slightly clayey soils. It is more tolerant of soil salinity than wheat and very tolerant of calcium
pH: The most suitable pH is between 6.5 and 7.5.
Climate: Barley is a widely adaptable crop. It is currently popular in temperate areas where it is grown as a summer crop and tropical areas where it is sown as a winter crop. Its germination time is one to three days and it requires a minimum temperature of 6ºC. It blooms at 16ºC and matures at 20ºC. Barley grows under cool conditions (until -10ºC), but is not particularly winter hardy.