Cherry Tree Water Requirements

Cherry trees, especially sweet cherries, need sufficient water to grow and produce high yields. Proper irrigation management is essential for successfully cultivating cherries, impacting both tree growth and fruit production. Understanding the critical periods for water sufficiency and the types of irrigation systems can help optimize cherry orchard management.

Importance of Irrigation in Cherry Orchards

Cherry trees respond significantly to water supply, resulting in vigorous growth and increased production.

First-Year of Establishment:

It is important to know that regular irrigation during the first year of plant establishment is required in many cases, especially in early spring, during summer, and sometimes during the first months of autumn when the water demand is higher.
Early spring irrigation supports bud development, while summer irrigation promotes root and vegetative growth.

Flowering and Fruit Development:

Adequate water during flowering and fruit formation is essential to support larger fruit production and reduce surface pitting risk.
Insufficient water during flowering can lead to poor fruit set, while water shortages during fruit development can reduce fruit size and quality.

Pre-Harvest and Post-Harvest:

Farmers should stop irrigation 5-7 days before harvesting the fruits to prevent fruit softening due to excessive water concentration. In some cases, farmers apply irrigation close to the harvest to boost fruit size and delay harvesting.
Post-harvest irrigation should continue at 3-4 week intervals during the warmer and driest summer months to support tree recovery and nutrient storage for the next season. Growers mention that this period is especially important, and the trees have very high water needs. If there is not sufficient rainfall, irrigation should be applied. At the same time, farmers avoid any soil disturbance (e.g. tillage) during this period to avoid soil moisture losses due to evaporation. If drought conditions persist into autumn, irrigation may continue until leaf drop begins. This ensures trees enter dormancy in a healthy state, with sufficient moisture to sustain them.

Water Requirements

Even though mature cherry trees are resilient and can survive droughts, it is sometimes crucial to provide them with adequate water to grow. In areas with insufficient (less than 1 inch or 25.4 mm of rain per week/10 days) or unevenly spread rainfalls during spring, cherry growers may have to start irrigating their orchards from early spring at the start of the flowering stage.

Annual Irrigation Rates:

In very low-density cherry orchards, the average annual irrigation rate is around 1,300 m³ per hectare (520 m³ per acre).

When rainfall is evenly distributed during the growing season, irrigation needs decrease. In such cases, farmers may only need to irrigate 1-2 times during fruit formation and another 1-2 times during summer drought spells.

However, it is important to remember that cherry trees are sensitive to excessive soil moisture, which can lead to root rots. Therefore, irrigation schedules and water amounts should be adapted based on seasonal tree needs, soil type, rainfall, tree age, and expected yield. A tensiometer can be a useful tool to develop a suitable irrigation schedule by monitoring soil moisture levels.

Types of Irrigation Systems for Cherry Orchards

Several irrigation systems are used in cherry orchards. The choice of system often depends on factors such as orchard size, water availability, and local climate conditions. Keep in mind that the tree roots of cherries are quite shallow and well-spread. In either system, it is important to spread the water up to a meter around the trunk and avoid wetting the tree trunk. At the same time, it is essential that the farmer takes measures to maintain good soil moisture and decrease evaporation. Mulching and reduced or no tillage can be beneficial. Many farmers prefer to chop weeds on their fields during summer and leave the cut plant residues on the top of the soil (as a mulch).

Basin and Furrow Irrigation:

This traditional method involves creating basins or furrows around the tree trunk to distribute water. While effective, it requires careful management to avoid over-irrigation and soil erosion. This system might be preferred in regions with good water availability and sufficient labor or in small orchards.

Drip Irrigation:

Drip irrigation is widely used in cherry orchards due to its high water use efficiency and precision. It minimizes evaporation losses and ensures even moisture distribution. In some states of N. America, farmers noticed that using a double-line drip system could save up to 58% of the water needed. Drip irrigation can allow the application of fertigation (an option that more and more farmers want to have).

Sprinkler Irrigation:

Small sprinklers or spray watering systems are used around the tree trunk to provide uniform water coverage. This method can be useful for cooling the orchard during hot weather and for frost protection during early spring. However, farmers must be extra careful when applying this method to avoid foliar fungal infection. Wetting of the tree canopy should be avoided during spring when the temperatures are mild and the risk of infections (e.g., from monilia) is high.

As far as sour cherries are concerned, a study showed that woodchip mulch and drip irrigation positively influenced the yielding of young sour cherries. The cultivars „Desertnaya Morozovoi‟, „Latvijas Zemais‟ and „Shokoladnica‟ were significantly more productive in woodchip mulch variant than in other variants due to rash vegetative growth in the previous year. Drip irrigation provided even growth and development of spurs, so it advanced the yielding of the cultivars „Bulatnikovskaya‟, „Zentenes‟, „Orlica‟ and„Tamaris‟. The cultivars „Latvijas Zemais‟ and „Orlica‟ were more resistant to twig blight than other cultivars. „Bulatnikovskaya‟ and „Tamaris‟ showed better resistance to cherry leaf spot than others. Drip irrigation slightly improved resistance to cherry leaf spot for the cultivars „Zentenes‟, „Orlica‟ and „Tamaris‟.

By understanding the critical periods of water need, utilizing appropriate irrigation systems, and adopting best practices, cherry growers can optimize tree health, fruit quality, and orchard productivity.

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