It’s Pistachio nut harvest time in the San Joaquin Valley of California, and the early crop report is not too exciting. The Western Farm Press is reporting the main problem with this year’s crop seems to be last year’s mild winter, among other problems.
Jeff Schmiederer, who has 700 acres of family owned pistachio trees in the western side of the valley says 90 percent of the nuts he has sampled are hollow, or what growers call “blanks.” “I’ve never seen a year this bad for blanks,” says Schmiederer. He and his family have been farming pistachios since the mid-1990s.
Richard Matoian, executive director of the Fresno, Calif.-based industry group American Pistachio Growers, says growers always find some hollow nuts, but they are within an acceptable level of about 10 percent of a crop. However, this year’s crop could run 50 percent of the nuts being blanks says Matoian. He estimates the 2015 crop coming in at 300 million pounds or less, down from 520 million pounds in 2014.
Last year’s unusually balmy winter was the main problem because pistachio trees need a period of “chilling” during what is supposed to be the cold winter months. This period of time is essential for the male and female trees to bloom properly and pollinate. Hollow nuts are the result of not having a “chilling” period.
If winter temperatures don’t provide the minimum chilling requirements, then the male trees, which are scattered among the female trees, “malfunction.” Actually, the male trees will bloom and pollinate, releasing pollen, but it’s at the wrong time, and usually after the females trees have bloomed.
Matoian adds, “It could be compared to a bunch of guys going to a party, but getting there late — after all the girls have gone home.”
Those hollow nuts can fool an inexperienced farmer. Pistachio trees always produce nuts, but unless optimal conditions are met, the nut shells will be empty. It is after harvest when the truth wins out, though. As part of the production process, the pistachios are dumped into a water bath. Blank shells float while the shells full of that good nut meat sink.
California is home to 99 percent of the nation’s pistachio orchards. Not all the orchards have been affected by the too mild winter, though. Orchards in the lower elevations of the San Joaquin Valley are doing well this year, as are orchards in Arizona. Arizona growers are expecting a yield this year equal to last year’s crop.
