Irrigation is an important factor to produce a good yield of quality jujubes.
Irrigation scheduling has a direct impact on tree health and fruit yield, size and quality. Without correct scheduling an orchard is more susceptible to nutrient deficiencies, physiological disorders, pests and diseases.
Correct irrigation scheduling requires an understanding of how much water:
- can be held in the root zone and used by the tree (readily available water)
- is required by the tree each day
- is applied by the irrigation system.
Jujube trees can survive with very little water, however, strategic irrigation can improve fruit set, reduce fruit drop and improve fruit size, yield and quality.
Trickle and drip irrigation are efficient, economical systems that are well suited to jujubes and have been used for the recommendations below. Micro sprinklers are also a good option for tree crops such as jujubes.
Scheduling depends on either measuring soil moisture in the root zone with a moisture meter, or measuring daily evaporation rates. The measurement is combined with a ‘crop factor’, which is a measure of the crop's water harvesting characteristics. It is affected by the root structure and the size of the soil volume from which the roots can extract water.