Irrigating Fruit Trees After Planting and During the First Year

Fruit Tree Establishment

During the first few weeks after planting, new roots must grow from older roots and into the soil used for planting. Learn how to plant fruit trees here. The growth of new roots from older roots and into the surrounding soil after planting is called fruit tree establishment. New roots can only grow from healthy, living roots. The smallest roots are fragile, resembling hairs, and are called feeder roots. See some feeder roots here. Feeder roots are responsible for most of the water and fertilizer taken from the soil and transported to the leaves. Feeder roots do not survive for more than a few minutes without soil, air and water surrounding them.

During planting it is normal that feeder roots and some of the larger roots will die. As the amount of time that roots are not in moist soil increases, more roots and more roots begin to die. As more roots die, the time needed for establishment increases and leaf and stem growth is delayed or the tree may become damaged.

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Fruit tree establishment takes time after planting. Fruit trees use energy stored in the roots for establishment. This same energy is used by fruit trees to grow new leaves and stems. Energy must be shared between the growth of the roots and growth of leaves and stems. The more energy needed by roots for establishment means less energy is available for the growth of leaves and stems.

After planting, fruit trees favor root growth more than leaf and stem growth. After the roots have grown significantly and can absorb enough water and nutrients, leaf and stem growth become increasingly more vigorous. Rapid and vigorous leaf and stem growth after planting is an indicator that roots have become established in the soil. This observation is when the Orchard manager can claim that the fruit tree has become established.

The time of day and weather conditions at planting time also affects establishment. The ideal conditions for planting fruit trees is early in the morning when temperatures are cool, the sky is cloudy and there is very little wind. Warm temperatures, bright sunlight and strong winds are the worst conditions for planting.

Irrigation after Planting

Drip irrigation on almonds. The first 2 to 3 years only requires one drip line. As they get older they will require two drip lines, one on either side of the tree.

All fruit trees must be irrigated immediately after planting. The reasons for this are several. When fruit trees are planted and soil is placed around the roots by hand or with machinery, large spaces filled with air are left in the soil surrounding the roots. If spaces in the soil are too large to hold water, tree roots cannot grow into these spaces.

Micro sprinkler beneath fruit trees.

Wetted area from a micro sprinkler on almonds.

Sprinkler from Jain irrigation

It is very important to collapse these spaces around the roots of trees. This helps the tree to remain upright and the collapsed soil surrounding the roots can more easily hold water. The easiest way to collapse these spaces is through irrigation. Irrigating the soil around the roots helps to collapse air spaces around the roots. After soil spaces have collapsed, roots can grow into these spaces and take water and nutrients.

To maintain rapid growth after establishment, adequate amounts of water is needed by the roots. Watering too frequently results in the roots “drowning” or suffocating from a lack of air. Not watering frequently enough results in roots dying from dehydration or a lack of water. The Orchard manager must determine when to irrigate with observations of the soil, not the tree. If the fruit tree shows signs that water is needed such as the dropping of leaves or wilting, establishment will be slow.

It is best to judge when to irrigate by observing the soil. The ideal time for the second and following irrigations can be determined easily by using a shovel, a sample of the soil and your hands. Use the shovel to dig and remove a handful of soil at the depth of the roots close to a tree. Squeeze the soil tightly with your hand. Lightly bounce the soil in your hand. If the soil falls apart easily after bouncing, it is time to irrigate. Soils that contain a lot of sand must be irrigated more often than soils which do not. As the summer months approach, fruit trees real require irrigations more often.