During this time of continuing drought and limited water availability, a question arises regarding the importance of and need for winter irrigation during dormancy.
Carbohydrate metabolism and mobilization in the tree, which occurs prior to bloom, is dependent on water. However, how almonds respond to water during dormancy and the extent to which water stress at this time impacts tree growth and yield is not well documented.
Current research efforts under the leadership of Ken Shackel of the University of California, Davis are quantifying how almonds respond to water during dormancy.
Until the topic is better understood, a precautionary approach was suggested by Shackel and fellow panelists Ted DeJong and Bruce Lampinen of the Department of Plant Sciences at UC Davis during the 2014 Almond Conference’s “Drought Tree Effects” symposium.
Growers should wait until 3-4 weeks before bloom. If it hasn’t rained enough, irrigate to fill the soil profile to two feet. If rains follow, there will still be room for more water.
If salinity is an issue, the best approach is to leach the salts further down if a sufficient quantity of higher-quality irrigation water is available.