If planting damage is likely to occur during periods of prolonged drought, watering should be done. By doing this periodically (weekly) the plants become accustomed to it not being done daily and root deeply. If watering is done late in the day and the temperature drops, evaporation losses are lower. Nowadays, underground irrigation through perforated pipes is used to save water and reduce evaporation.
Species can be grouped according to water requirements; irrigation policies can be adjusted accordingly.