In the third week of August, while pistachio growers in Arizona and California were still waiting for their slow-to-mature crop to ripen, in New Mexico, near Alamogordo, Eagle Ranch Pistachio Groves’s two shakers had already begun harvesting nuts — two weeks earlier than usual.
“It’s a good harvest, and the nuts have turned out well,” says Marianne Schweers. She and her husband, George, own and manage 85 acres of pistachios.
They also have their own on-farm facilities to hull, dry, roast, salt and package the nuts, mostly for retail sales.
“An earlier harvest is always better for us,” she says. “Getting a two-week head start on the holiday season is absolutely a blessing.”
Before the season started, the Schweers weren’t even sure they’d have a pistachio crop this year. For three days in early February, daytime temperatures never rose above freezing. One night, temperatures plummeted to 12 degrees below zero, then dropped 2 degrees lower another night. “We didn’t know what that cold would do to the trees,” Marianne says.
As it turned out, they lost only about a dozen trees, which they had already identified as stressed and under-producing.
However, their eight year-old vineyards weren’t so fortunate. The Schweers grow seven red and white varieties of grapes, which they make into wine and bottle under their Heart of the Desert Vineyards label. During the February cold snap, all 18,000 of their vines froze to the ground.
“Although we lost this year’s grape crop, about 80 percent to 85 percent of the vines have come back,” Marianne says. “So, we’ll have to replant some areas next spring.”
Eagle Ranch is the first and largest commercial pistachio orchard in New Mexico, she says. Their first trees were planted in 1972. Representing a mix of on- and off-year production cycles, they now have about 12,000 trees, all Kerman, spaced from 17 x 17-feet to 24 x 24-feet.
This year’s early harvest follows an early leaf-out, which occurred mid-March, about two weeks sooner than usual.
The Schweers asked pistachio expert Bob Beede, University of California Cooperative Extension farm advisor for Kings County, Calif., if he had an explanation for the early harvest this year. He suspects it’s related to warmer temperatures in the spring, following the freezing February weather
A peach fruit development model created by Ted DeJong, University of California Cooperative Extension pomologist, showed spring temperatures had a pronounced effect on maturity date and fruit size, Beede says. Examination of degree-day accumulation over several seasons has led him to believe the same relationship exists in pistachios and walnuts. Cold springs delay maturity and warm ones advance it, regardless of summer temperatures/
“We haven’t done any detailed studies with pistachios, but the findings from shipping peaches seem to apply also to pistachios and other nut crops,” he says
In fact, when the Schweers reviewed records from their on-farm weather station, they found that temperatures this spring were as much as 10 degrees warmer than normal.
Based on the first week of this year’s harvest, Marianne rates nut quality above average. Initial testing showed a split rate of 75 percent to 80 percent.
“Usually, we get a little better than that, but this was just the first sample,” she says. The nut size, 21 to 25, is normal.
“We don’t have the high production values you see in California,” Marianne says. “We’re happy to get 2,500 pounds per acre. The first field we shook this year produced about 3,000 pounds per acre, but it’s in an on-year. That volume won’t hold through all of our groves.”
The Schweers haven’t had to contend with any disease problems this year. Normally, stink bugs and leaffooted plant bugs require control, but not this year. “We’ve have no insect problems,” she says. “We think that’s the result of the cold weather this past winter.”
They sell some of their nuts to wholesalers, but market the bulk of their crop directly to consumers, much of it through their three stores, one on-farm and two in Las Cruces, N.M., about 70 miles away.”Around 30 percent of our retail business is done on the Web,” she says.