Why There are three main reasons to use irrigation trigger points on your orchard - environmental responsibility, cost saving and planning. Water resources are limited. Often water restrictions apply in Hawke's Bay over dry seasons and it is essential for all users to conserve water. In order to do this orchardists can apply a certain amount of water stress to fruit trees. Results from last years work indicate that using this technique does not influence fruit quality.
Irrigation also costs.
If irrigation is applied only when necessary the trigger point technique provides a cost minimising service. Finally, the trigger point method can assist in planning the irrigation schedule for the orchard. By knowing your trigger points and monitoring the soil moisture over the orchard a priority schedule for irrigating can be made. After finding the trigger point for a set of trees all you need to do is keep checking your soil moisture over the season and irrigate when you reach the trigger point. How The basic concept for the method is to measure fruit growth and soil moisture for trees that are irrigated normally, and for trees that aren't irrigated at all.