 Alfalfa balers can plant for afternoon humidity to dip between 15 and 20% most days, and humidity will be only briefly above 60% during the late night hours. Irrigators can expect weekly crop water use to range between 2 1⁄2 and 2 3⁄4 inches for alfalfa, onions, potatoes, corn, and apples, while lawns will need 2 to 2 1⁄4 inches, and melons and wine grapes an inch and 3 quarters to 2 inches.