Continued growth predicted for organic blueberries

Demand for organic blueberries is on the rise. In 2014-15, California produced 8.4 million pounds of organic blueberries, and one year later, organic production rose to 9.4 million pounds.

"We're definitely seeing an increase in organics in California, in terms of picking, packing, shipping," said Alex Ott, executive director of the California Blueberry Commission.

Ott said he anticipates this year's crop will exceed the 2015-16 crop.

Chad Hansen, blueberry category director for Homegrown Organic Farms, agreed the organic blueberry market is growing, and he's seen double-digit growth in volume over the past five to six years.

"We anticipate continued growth in the coming years as well," Hansen said, in the domestic and international markets.

In California, more organic blueberries are being harvested, and there are more organics going into the ground, Ott said.

Blueberries are still hand-harvested, but mechanical harvesting is also done, Ott said.

"Because of increased labor costs and also a decrease in labor workers and availability, we are starting to see more and more mechanical harvest come on," he said.

Many times, growers hand-pick the first or second pick, then for the third or fourth pick they will use a mechanical harvester, Ott said.

"The biggest expense to any grower is that of labor, and as long as you continue to have regulatory challenges, as long as you continue to have increased rules, regulations and mandates, growers are going to look for innovative ways to continue to produce a high-quality crop, while at the same time, reduce costs," he said.

Hansen agreed labor is a challenge.

"Everything needs to pencil out because if the grower isn't making money, he isn't going to grow," he said.

Ben Faber, University of California Cooperative Extension farm advisor in Ventura County, said blueberries are a very persnickety plant.

"It's got a very shallow root system, and it's got to be irrigated just according to its needs, not according to what your irrigation cycle is," Faber said.

Blueberries are also very particular about the pH of the soil. They want a pH of around 4.0, but some soils have a pH of 7.0 and higher, Faber said.

"Before you ever think of planting, get the pH down to around 4.0," Faber advised.

For a conventional grower, there are several different sources of acid modifiers available to reduce the soil pH, but organic growers are limited to the use of organically approved sulfur.

Blueberries with a high pH will turn yellow and purplish, then the leaves drop and the plant dies back, Faber said.

The pH is incredibly difficult to change once the plants are in the ground without killing the plants, because acid is used to bring the pH down and it will burn the roots, he said.

"It's critical to get the pH right before you plant," Faber stressed, adding, "You pay later for rushing into planting before the pH is right."

There are some areas with naturally low pH—along the coastal area of San Diego, and on the east side up against the Sierra, Faber said.

"The pHs tend to be around 6.5, 6.6. That's great for most plants, but blueberries want pH 4," Faber said.

John Carlon and his wife. Armen, are owners of Sierra Cascade Blueberry Farm in Forest Ranch.

Carlon's farm is in the foothills of the Sierra, and that's important, he said, because the volcanic soils means their pH is fairly low.

"It's naturally like 6.0 or 5.5, and so we just have to bring it down a little bit," he said.

Carlon has also found that pH is really varietal-specific.

"Some of the varieties we have, have classic iron chlorosis deficiency from having the pH too high, and another variety right next to it is doing great," Carlon said, adding just a tenth of a point in pH can be a big deal for certain varieties.

Carlon's farm is at about 2,300 feet elevation, which is an advantage when it comes to winter chilling, too. He doesn't use any herbicides, pesticides, fertilizers—organic or otherwise. He irrigates, mows and, about every four to five years, he adds elemental sulfur to bring the pH back down.

David Haviland, UCCE farm advisor, said organic blueberry growers have some pests to content with.

Citrus thrips mainly affect the new growth of the plant. They will stunt the plants and reduce yields the following year, Haviland said. They are mainly controlled with Spinosad (Entrust), he added.

"Thrips for organics are difficult. Biological control for citrus thrips is negligible in blueberries. So it comes down to really tolerating damage and using Spinosad," Haviland said.

"Thrips is a problem pretty much every year for blueberry growers in the Central Valley," Haviland continued, but it's not an issue for coastal growers where they have a cooler climate.

Spinosad is a very good product if it isn't overused, Haviland said, but there are documented cases in the Central Valley that the citrus thrips have developed full resistance to all Spinosyns, including Spinosad.

While the coastal areas have fewer problems with thrips, they have more problems with spotted-wing drosophila, he said.

Spotted-wing drosophila is also controlled with Spinosad, and applications are made before harvest to protect the fruit, Haviland said.

There are no bio- or cultural controls for spotted-wing drosophila.

"It's just a matter of spraying when you need to, based on traps and monitoring," Haviland said.

The other blueberry pest in the Central Valley is the white grub, which is controlled with entomopathogenic nematodes, Haviland said.

"They are quite effective on the grubs, and that's registered on organic," he said.

The nematodes are injected through the irrigation system into the soil. Once the nematodes are in the soil, they seek out the grubs, enter in through the spiracles and mass reproduce, Haviland said.

They basically turn the inside of the grub into spaghetti; then those nematodes will crawl out and seek out more grubs to infect, Haviland said.

"It's actually a very efficient system and even the conventional growers commonly use the organically approved beneficial nematodes," Haviland said.

(Kathy Coatney is a reporter in Bend, Ore. She may be contacted at kacoatney@gmail.com.)