Weather last month in the Kettleman City area, in western Kings County where California Pistachio Orchards is located, wasn’t boring.
“It was interesting to say the least,” says Chris Couture. “We saw frost, 99 degree temperatures and hailstorms. Fortunately, the main hail event that swept through the San Joaquin Valley earlier in the month, with golf ball-size hail, missed us.
“By the end of April, our trees had finished bloom and pollination; they look healthy, with good color. Now we’re waiting to see what percentage of the nuts set and later fill.”
He and his brother, Steve, operate the fourth-generation family partnership, which has been growing and processing pistachios since 1976. Dating back to 1910, the farm also produces almonds, pomegranates and asparagus. Like pistachios, these drip-irrigated crops are grown using organic practices.
Their father, Paul, planted the farm’s first pistachio trees 40 years ago on the only rootstock available at the time — Atlantica. Due to its susceptibility to verticillium wilt, the orchards were replanted in 1979 on Integerrima rootstock. Some of the original trees planted in 1972 are still standing.
Today, the Coutures have 310 aces of organic pistachio trees — 150 acres of the original planting and another 160 acres, established five years ago, that will be harvested for the first time this year.
Unlike the alternating years of on and off production typical of many pistachio orchards in the state, their yields have been much less variable — averaging between 2,800 and 3,200 pounds per acre for the last several years. “Hopefully, that trend will continue,” Chris says.
The pistachio bloom this year started around April 10. To encourage early bloom, Chris applies organic oils. Because of their higher elevation, the orchards often don’t receive sufficient chilling hours in the winter for proper bloom and nut formation. Also, since the Coutures farm organically, they like to harvest early to avoid navel orangeworm pressure.
He’ll take petiole samples this month to determine fertilizer needs of the trees. Currently, he’s applying 10 tons of compost per acre during the dormant season. During the growing season, he sprays orchards with organic zinc and boron, and makes a weekly application of organic compost tea through the drip system. In the fall, he treats with an organic zinc leaf burn.
Weed control is a challenge. “We spend a huge amount of money hand-weeding broadleaf weeds,” Chris says. “Also, we use propane flamers down the tree row, and we mow the middles.”
The dry climate of his west side location means very little pressure from diseases, including botryosphaeria. He ignores pressure from early-season pests, lygus and phytocoris plant bugs.
“In our experience, the damage they do is limited to several nuts on a cluster, which the tree compensates for. In July, we treat for citrus flat mite with organic sulfur compounds.”
The Couture farm lies within the Westlands Water District. Like other growers in this part of the San Joaquin Valley, they’re not happy with the amount of surface water they’ll have to irrigate their trees this year. “We’re expecting only a 40 percent allocation, or 1.04 acre-feet,” Chris says. “Precipitation has been near normal in northern California and the reservoirs are above historical average. Those of us who farm south of the Delta should be able to receive better allocations and still leave enough water to protect wildlife.”
Between bloom and fill, he will irrigate at close to 50 percent evapotranspiration. Then, he hopes to find sufficient water to irrigate at 100 percent ET to split the pistachios.