By Mary Schrieber
The combination of a late freeze and a lack of chill hours will likely lead to reduced fruit yields across the state, according to a Texas A&M AgriLife Extension Service expert.
Tim Hartmann, Ph.D., AgriLife Extension statewide fruit specialist and assistant professor in the Texas A&M College of Agriculture and Life Sciences Department of Horticultural Sciences, has been connecting with fruit producers and tracking reported chill hours. He emphasized the importance of favorable weather conditions for fruit production.
Temperate fruit crops like peaches, apples, blackberries and blueberries require exposure to cool conditions, causing the plants to go dormant and enabling them to survive the winter weather.
Chill hours issues
Chilling refers to the exposure of plants to this cool weather to overcome dormancy requirements. While there are many models to quantify chilling, the simplest is chill hours, defined as the number of hours in which temperatures remain below 45 degrees during winter.
The chill hours required for each fruit and variety vary; peaches in South Texas may require as few as 200 hours, while another peach variety grown along the Red River may need over 1,000 hours for a good fruit set, Hartmann said.
Improper exposure to cooler weather leads to delayed and sporadic bud break, weak vegetative growth, poor fruit set and abnormal fruit development, ultimately resulting in reduced or, in some cases, zero yield.
Source : tamu.edu