Exodus 9:31

Flax] Largely grown for making linen which was worn by the priests, and used, among other purposes, for swathing mummies. The word rendered boiled, i.e. podded, is explained in RM as meaning 'was in bloom.' It means, rather, 'was in bud.' Flax flowers as a rule in February, and barley comes into ear about the same time. Wheat is a month later than barley, and spelt (here incorrectly called rie, which is not grown in Egypt) is sown and ripens at the same time as wheat. The condition of the crops indicated here fixes the time of the plague at about the end of January.