A Technical Report from The Bartlett Tree Research Laboratories
The best way to maintain tree health during drought periods is also the simplest: provide additional water when the soil dries and add mulch appropriately to conserve soil moisture. Of course, simply adding more water is not always feasible when environmental stewardship and water use restrictions come into consideration. Fortunately, most mature trees in arid or Mediterranean climates are adapted to long periods without rain, making supplemental irrigation unnecessary under moderate drought conditions. However, even drought-tolerant species will suffer under prolonged water shortage.