Impact of Chilling Requirement On Fruit Quality

Plants shed their leaves in order to survive the cold winter months. This process plants are going through is called dormancy period. A dormant plant cannot perform normal life activities such as flowering, fruit setting and budding. The dormancy period continues until the necessary duration of cooling has been passed.

The chilling requirement varies from species to species, varieties to varieties. That is why it is crucial to decide which variety suitable to where. For instance, if we assume that the variety has a chilling requirement lower than the region it is planted; the variety will cause early spring budding and early flowering. This will increase the risk of getting harmed by the early spring frosts and colds. Let's assume the opposite; the variety has a chilling requirement higher than the region it is planted. In that case, there will be a real insufficiency in its quality, largeness and fruit set. Chilling durations of the plantation area and the variety should be similar. 

The chill hours of a region depends on so many different variables so it is hard to measure. Calculations are made according to expected values. The most common method is to calculate the dormancy period of the plant under 7,2 degree.

Most of the fruit varieties require high chill hours (800 – 1000 hours) but there are varieties that need fewer chill hours; varieties that require chill hours less than 500 hours are the ones that require lower chilling degrees. In the coastal areas and in southern regions chilling period decreases to 300 hours and varieties that need low chilling degrees should be preferred.

One of the important points to take into consideration when creating a fruit garden is the chilling time variety requires. For this reason, it is important to ask for information from the experienced fruit garden owners, agricultural research agencies and your sapling supplier.