The term refers to the number of hours during winter when temperatures are below 45F (7C) but above freezing (32F or 0C). This period of cold is crucial for the successful cultivation of certain fruit varieties. For instance, a specific type of fruit tree might require a defined accumulation of these cold hours to break dormancy and initiate proper bud development and subsequent fruit production. The Fuji apple is one such cultivar impacted by this requirement.
Adequate exposure to these cold temperatures is vital for reliable and abundant harvests. Without sufficient chilling, the tree may exhibit delayed or uneven bud break, leading to reduced fruit set and diminished yields. Furthermore, the quality of the fruit itself can be negatively affected, with issues such as poor color development or irregular ripening. Historically, understanding and adapting to regional climate conditions and the cold requirements of fruit trees has been a cornerstone of successful orchard management.
