Planting at the optimum time is probably the most important cultural practice in producing high small grain yields. Wheat and barley crops that are planted too early or too late have lower yield potential no matter how they are grown after planting. However, small grains are sometimes planted later than optimum when grown in rotation with cotton or vegetables due to harvest timing in these crops. Therefore, the entire farm enterprise should be considered when deciding on a planting date for small grains.
A publication on planting dates for small grains in Arizona can be found at the following link PDF