It is difficult to give hard and fast rules however, because individual crops and individual areas vary so greatly. When irrigating, it is important to consider watering efficiently. The ripening of the crop all at the same time improves ease of management, increases efficiency of harvest and saves money. B. Knowing when to irrigate. Determining when to irrigate and how much water to apply are the main problems in irrigating.
Timing is critical.
Snap beans, if under moisture stress during flowering and pod formation, suffer a depressed yield because of ovule abortion and flower abscission. Berries of grapes will not reach full size if the root zone is at W.P. during the berry enlarging period. There are several methods used to determine when to irrigate. Leaves will curl. Shoot tips will become harder and darker sometimes with a grey cast and sometimes lose turgor.