Message from SE Area Pecan Agent, Andrew Sawyer
Pecans generally are not fooled by temperature through the last frost. Sometimes, they will be fooled and break bud before Easter. Interestingly, pecan budbreak involves both cold and warm temperatures. It does not take much cold units for pecan as it does peaches. Pecan budbreak can occur with 100 cold hours, which is not much. But the heat units in the Spring influence budbreak more than the cold units in the winter. If we have a cold winter with high amounts of cold hours, then less heat units are required to make pecan budbreak. The opposite is true regarding fewer cold hours as well.
I’m hearing of some pecan trees attempting to break bud now ahead of a predicted cold weather with lows in the 30s. Will this hurt the trees? Cold temperature affects either 1) the cambium under bark of young trees and 2) tender foliage following budbreak. If flowers are damaged, this will hurt the crop. Considering mature trees, we generally need to see temperatures drop below 30 degrees (maybe 28) before tender foliage can be damaged. It also depends on how much foliage has come out. The bud will be more tolerant of the cold temperature than the foliage itself.
For more information take a look at these old blog posts from the Pecan Team OR contact your local County Extension Office
