When The best time to water is at night from 10 p.m. to 8 a.m. Watering at night allows less evaporative loss of water, so more water moves into the tree. Any water shortage in the tree will usually be removed overnight. These application hours also minimize pest problems on ground covers and turf. Trees use water night and day, season to season, whether leaves are present or not.
Trees use water all year.
Dormant season water during winter droughts can help your trees. Fine soils require careful attention to prevent over-watering and root death. How Often Trees should be watered once or twice a week in the growing season if there is no rainfall. A few heavy waterings are much better than many light, shallow waterings. A greater proportion of the applied water is utilized by the trees with heavy watering.