San Joaquin County is the leading walnut-producing county in California and favorable weather is pointing to another good crop.
“The trees seem to be pretty well loaded with nuts this year,” says Joe Grant, UC Cooperative Extension Farm Advisor for the county. “That’s pretty much the case up and down the state — we’ve had a good growing season so far.”
Following a long, cool spring, the county hasn’t had too much extremely hot weather. “Normally, during July and August, we can easily have 7 to 10 days a month with temperatures above 100 degrees,” Grant says. “But this year, through the end of July, the weather has remained a little on the cool side, with very few 100-degree or hotter days. If we can keep that kind of weather, we can keep the walnuts in good condition.”
Assuming that’s the case, this year’s crop could be the third big one in a row.
The crop load across all walnut varieties in San Joaquin County appears to range from moderate to heavy, Grant notes.
Though cool weather caused the Chandler bloom to be a little straggly, there’s not much variation in nut size, as would be expected for a straggly bloom, he says. And, rains during Serr bloom minimized the incidence of pistillate flower abscission (PFA), which is caused by excess pollen loads in Serr and other varieties.
Except for some growers who were surprised by heavier late season walnut blight, most have experienced no unusual disease or insect problems, but Grant points out that coddling moths, mites and walnut husk flies could still pose late season threats to many orchards.
He expects harvest in his county to begin with the early varieties in mid-September, a little later than normal. “Overall, I think most growers are looking forward to a good harvest season,” Grant says.