Watering correctly is critical to the development of good quality fruit and allows trees to preserve a natural resistance to fungal diseases. Underwatering produces fruit that is small, and fruit will tend to sunburn. Overwatering predisposes the tree to root and crown rots.
During the heat of summer, avocados will require about 2 inches of water per week for a mature tree. Citrus will require about 4 to 6 inches of water per month. However, depending upon your soil type, this amount may be divided up into several applications.
Ideally, in hot summer climate zones, you may want to irrigate about every 7 to 10 days during the middle of the summer. You may irrigate your trees using a drip system with either two to four emitters per tree or using small microspray emitters. Under a drip system, a tree may require 45 to 60 gallons per day in the heat of summer, depending upon the climate zone and soil characteristics. The root zone of avocado and citrus trees is shallow and drippers need to be placed at the base of the trunk on newly planted trees to keep the root ball moist until roots grow into the native soil. Apply water further from the tree trunk as trees become established.
