Cherry trees, native to cooler, temperate climates, face a significant challenge when grown in an arid and hot environment like Arizona. It is possible, however, under specific, carefully managed conditions. Success depends entirely on selecting the right genetic variety and placing the tree in one of Arizona’s geographically cooler microclimates. The difficulty lies in balancing the tree’s biological need for winter cold with the region’s high temperatures and intense summer sun. Overcoming these obstacles requires a strategic approach addressing the tree’s dormancy requirements and its ongoing care in a desert landscape.
Arizona’s Climate Divide and Cherry Suitability
Arizona’s vast landscape is characterized by a dramatic climate divide, which is the primary factor determining where a cherry tree can thrive. The state’s lower elevations, including Phoenix and Tucson, are classified as the Low Desert, receiving insufficient winter cold for most traditional cherry varieties. High summer heat in these regions also presents a major survival barrier.
The most viable locations are in the higher elevations, such as the northern and central parts of the state (e.g., Yavapai County or the White Mountains). These regions, typically above 4,000 feet, experience the colder winter climate necessary for the tree’s reproductive cycle. Areas between 4,000 and 6,000 feet can support varieties requiring 750 to 1,000 chill hours. This geographical distinction separates the possibility of a fruitful harvest from a simple ornamental tree struggling to survive.
Understanding Chill Hours: The Key Limiting Factor
The fundamental biological barrier for growing cherries in warmer climates is the requirement for “chill hours.” A chill hour is defined as an hour between 32°F and 45°F during the winter dormancy period. Deciduous fruit trees need this accumulation of cold to break down natural growth inhibitors within their flower and leaf buds.
Traditional sweet cherry varieties, such as ‘Bing,’ typically require 700 to 1,200 chill hours to ensure proper flowering and fruit set. Insufficient chilling can cause symptoms like uneven bud break, delayed leafing, or a significantly reduced fruit yield. In the Low Desert, where cold hour accumulation is inconsistent, the tree’s biological clock is not properly reset, leading to poor performance.
Low-Chill Cherry Varieties for Arizona
To counteract the challenge of low winter chilling, growers must select specific cultivars bred to require significantly fewer cold hours. These low-chill varieties are the only realistic option for Arizona’s warmer regions, as they reliably set fruit with limited cold. The newest low-chill sweet cherry varieties often require only 200 to 300 chill hours to bloom.
Two examples are ‘Minnie Royal’ and ‘Royal Lee,’ which require cross-pollination and are often planted together. ‘Royal Crimson’ is another suitable option; it is a self-fruitful variety with a similar low chill requirement, making it an excellent choice for a single-tree planting. For those in slightly cooler microclimates, the ‘Lapins’ variety is a popular self-fruitful option that needs approximately 350 to 400 chill hours.
Essential Care Practices for Desert Cherry Trees
Even with the correct low-chill variety, cherry trees in Arizona require specific care to manage the intense heat and arid soil conditions. The deep, well-draining soil with a neutral pH between 6.0 and 7.0 that cherries prefer is often not naturally present in the desert, necessitating significant soil amendment with organic matter before planting. Good drainage is paramount, as cherry trees are highly susceptible to fungal root rot if their roots remain in standing water.
Watering must be deep and consistent, preventing the soil from drying out, particularly during the hot summer months, the flowering period, and when the fruit is developing. Young trees need regular, deep irrigation to establish a robust root system. Protecting the trunk from sunscald is also necessary, accomplished by painting the trunk with a diluted white latex paint to reflect the harsh afternoon sun.
Pruning techniques must be adapted for the desert, focusing on encouraging a scaffold structure that allows for good air circulation and self-shading. Pruning should be done in late summer immediately after the sweet cherry harvest to minimize the risk of bacterial and fungal infections. Fertilization with a low-nitrogen formula, such as 5-10-10, can be applied early in the spring before flowering, but avoid application after mid-summer to ensure new growth has time to mature before winter.