Subtropical Fruit Crops Research & Education
University of California
Subtropical Fruit Crops Research & Education

Posts Tagged: California

Organic Blueberries Make More Money

Synopsis of: “The Organic Premium for California Blueberries” by Hoy Carmen, professor emeritus in the Agricultural and Resource Economics Dept., UC Davis

Commercial-scale production of blueberries in California is a relatively recent development. California first reported blueberry statistics in 2005 when there were 1,800 acres of blueberries harvested and production of 9.1 million pounds with a total value of $40.58 million. Harvested acres increased to 3,900 acres in 2010 with production of 28 million pounds and a total value of $75.98 million. Growth continued through 2015 with California Agricultural Statistics Survey (CASS) reporting 5,700 acres of blueberries harvested, production of 62.4 million pounds, and total value of $116.98 million.

California blueberries are shipped throughout the U.S. and to a number of export destinations. During the 2016 harvest, California's largest U.S. market was California, which accounted for 34.75% of California's total fresh blueberry shipments of 46,493,407 pounds.

The largest out-of-state domestic shipments were to Texas, Oregon, Washington, Arizona, New York, Minnesota, Utah, and Pennsylvania. These states collectively accounted for 36.54% of California shipments. Canadian shipments of 5.54 million pounds accounted for 11.9% of California's volume and made up 67.1% of exports.

Typically, the price per pound of organically grown blueberries is higher than for conventional production. Prices also vary by package size, with smaller package sizes usually selling for more per pound than larger packages. There is usually a premium for the first portion of the crop-marketing year, and the overall level of prices will vary by year. Prices can also be expected to vary by geographic location. California organic blueberries are among the first domestic fruit on the market when prices tend to be seasonally high.

Growth in California organic blueberry production has outpaced conventional production for several years, and California accounted for about half of the U.S. supply of organic blueberries in 2014. The organic share of California blueberry shipments in 2016 was 23.1% in terms of volume and 34.8% in terms of value. The larger share of value is due to the premium price for organic blueberries.

The organic premium, which averaged $2.28 per pound in both 2015 and 2016 (78–79% of the conventional fresh blueberry price), varies by package and over time. California has some of the earliest domestic blueberry production, with relatively high prices for both conventional and organic blueberries at the beginning of the season. The proportion of shipments that are organic decreases as the season progresses and the organic premium tends to be highest after the first one-third of the season. The growth of organic blueberry production in California, relative to overall California production as well as U.S. organic blueberry production, seems to indicate a comparative advantage for organic blueberries in California. Further growth of organic as well as total blueberry production in California is expected.


For the full article see:

Organic production costs, South Coast

Conventional costs, South Coast

Conventional, San Joaquin Valley

Report on US Organic Sales, 2016


Blueberry fruit
Blueberry fruit

Posted on Friday, October 6, 2017 at 7:20 AM
Tags: blueberry (7), California (12), conventional (2), costs (1), development (1), organic (12), prices (1), production costs (2), sales (3)

Avocado Grower Seminar Series – Ambrosia Beetle Seminar Coming to California

“Laurel wilt – A new threat to California's avocado industry”

Presented by: California Avocado Society, Inc., California Avocado Commission, University of California Cooperative Extension, and University of Florida's Tropical Research and Education Center. Event is FREE, everyone is welcome!

  • Tuesday, August 1, 2017, 1:00 p.m. to 3:00 p.m.,

UC Cooperative Extension Office Auditorium, 2156 Sierra Way, San Luis Obispo, CA 93401

  • Wednesday, August 2, 2017, 9:00 a.m. to 11:00 a.m.,

UC Cooperative Extension Office Auditorium, 669 County Square Dr. Ventura, CA 93003

  • Thursday, August 3, 2017, 1:00 p.m. to 3:00 p.m.,

Fallbrook Public Utility District Board Rm., 990 East Mission Rd. Fallbrook, CA 92028






Jeff Wasielewski, Subtropical Fruit Agent, University of Florida Extension

The current status of laurel wilt in South Florida


Randy Ploetz, Professor of Plant Pathology at the Tropical Research & Education Center of the Institute of Food & Agricultural Sciences (IFAS), University of Florida

Laurel wilt epidemiology and management


Bruce Schaffer, Professor of Ecophysiology of Subtropical and Tropical Horticultural Crops,IFAS, University of Florida


Vascular physiology and anatomy of different avocado genotypes relative to laurel wilt susceptibility


Daniel Carrillo, Professor of Entomology and Nematology in Subtropical and Tropical Horticultural Crops, IFAS, University of Florida



Laurel wilt vectors: biology and management


Edward Evans, professor in the Food and Resource Economics Department located at the University of Florida's Tropical Research and Education Center

Economic impact and economics of control strategies


Jonathan Crane, Professor of Horticulture / Tropical Fruit Crop Specialist, University of Florida's Tropical Research and Education Center

Current control strategies, recommendations and issues

Laurel Wilt Cycle
Laurel Wilt Cycle

Posted on Friday, July 14, 2017 at 7:26 AM

New Avocados for the Valley?

California avocados are the best in the world. So says downtown restaurant manager Daniel Avalos in a Valley Public Radio story by reporter Ezra David Romero.

The fact that they currently thrive only on a small swath of coastal Southern California is being challenged by UC Cooperative Extension specialist Mary Lu Arpaia. She is on a mission to find avocado varieties that withstand the hot summers and cold winters of the San Joaquin Valley, where irrigation water and crop land are more abundant and cheaper. 

She hopes to find avocado varieties that ripen at various times of year, and varieties that might be an alternative crop for citrus growers should huanglongbing, a disease that has devastated the Florida citrus crop, take hold in Central California.

"There's a void of California fruit on the market in the months of November, December and actually early January," Arpaia said. "So if we can find different selections that maybe are unique that fit into that window, then we help the entire California avocado industry."

An as-yet unnamed avocado variety. 

Romero visited the UC Lindcove Research and Extension Center to see the trees in Arpaia's study. Currently, the vast majority of California avocados are the Hass variety. The goal is to breed varieties with similar eating quality that grow to a moderate height and have high yield. One potential that is already being produced by nurseries is called "gem."

"This is gem," said Eric Focht, a staff research associate in Arpaia's lab. "You can see it's a little more oval or egg shaped than Hass. It has the speckling on the skin. Now as this ripens, it will turn dark and a lot of times the speckled lenticels with get a yellow kind of golden color it it."

Another promising variety is called "lunchbox" because of its small size. According to Focht, it "just falls out of the skin." Arpaia said, "It makes wonderful guacamole and I found, with a non-replicated test in my refrigerator, the fruit doesn't brown."

Arpaia's favorite guacamole recipe is featured at the end of the story on the KVPR website. And there is more on this story at:


Mary Lu Arpaia

Mary Lu
Mary Lu

Posted on Friday, May 12, 2017 at 5:46 AM
  • Author: Jeanette Warnert
Tags: avocado (278), California (12), citrus (316), freeze (9), frost (18), heat damage (4), irrigation (78), lemon (95), new crops (6), new variety (1), nutrients (21), nutrition (5), oranges (6), temperature control (1)

Xylella fastidiosa introduction to Europe traced back to Central America

Elizabeth Fichtner1, Dani Lightle2, Dan Flynn3, Rodrigo Krugner4

UC Cooperative Extension (UCCE) Tulare1, Kings1, Glenn2, Tehama2, and Butte2 Counties, UC Davis Olive Center3, USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center4


The recent outbreak of the plant bacterium Xylella fastidiosa in southern Italy illustrates the potential for introduced organisms to incite widespread havoc in a short time. Xylella fastidiosa has been found in association with a new disease called olive quick decline syndrome (OQDS), which is affecting over 20,000 acres of olive in the Apulia region of Italy. Symptoms of OQDS include extensive branch and twig dieback, yellow and brown lesions on leaf tips and margins, vascular discoloration, and subsequent tree mortality. In southern Italy, the main insect vector of X. fastidiosa is the spittlebug Philaenus spumarius, which is known to occur in California. While research is underway to determine if the bacterium is responsible for causing OQDS, establishment of X. fastidiosa in Europe leaves growers and researchers asking where it came from. Genetic techniques used to compare pathogen populations have led researchers to hypothesize that the isolates of X. fastidiosa (strain CoDiRO) associated with OQDS, may have originated in Costa Rica. Marking the first European find of X. fastidiosa outside of Italy, the bacterium also was found on ornamental coffee plants at a retail market near Paris in April 2015; the plants had been imported to Europe from Honduras (3). In July 2015, X. fastidiosa was identified on ornamental plants on the French island of Corsica and on the mainland in October 2015 (2). The X. fastidiosa subspecies found in Corsica (subspecies multiplex) is different from that associated with OQDS in Italy (subspecies pauca) (2).

The European Commission has imposed several regulatory actions to prevent further spread and introduction of X. fastidiosa into the European Union, including a specific ban on import of coffee plants from Honduras and Costa Rica; eradication measures in Italy and France; and the potential for strict eradication measures aimed at new outbreaks or finds of the bacterium, including removal and destruction of infected plants, and all host plants within a radius of 100 m. (1)

The new introductions of X. fastidiosa to Europe illustrate the potential for long distance dispersal of the bacterium and a vulnerability of California agriculture to invasion by new organisms. The United States Department of Agriculture-Animal and Plant Health Inspection Service-Plant Protection and Quarantine's (USDA-APHIS-PPQ) New Pest Advisory Group (NPAG) is assessing the biology and potential economic and environmental impacts that the strain CoDiRO may pose to the United States to recommend potential regulatory strategies (Tara Holz, personal communication).  NPAG is designed to inform Federal decision makers regarding potential regulatory actions that may be appropriate to prevent pest introduction.Previous USDA-led research has found X. fastidiosa in California olive trees, but the endemic bacterium has only limited association with disease and is a different subspecies than the CoRiDO strain associated with the OQDS in Italy.

California olive growers and industry stakeholders are encouraged to contact UCCE Farm Advisors to report trees displaying symptoms of OQDS.


1. European Commission Press Release, April 28, 2015:

2. European and Mediterranean Plant Protection Organization. 2015. First reports of Xylella fastidiosa in EPPO region-Special Alert.

3. French Ministry of Agriculture Food and Safety Press Release, April 29, 2015:


xylella f on olives
xylella f on olives

Posted on Wednesday, January 20, 2016 at 7:56 AM
  • Author: Elizabeth Fichtner
Tags: California (12), disease (57), olive (10), xylella fastidiosa (1)

Cold Tolerant Avocado Varieties?

Avocado is a fruit tree that is notable for its sensitivity to cold. There are tropical varieities that are very sensitive to cold most notably many of the varieties that are of a West Indian origin. The subtropical varieites that are grown in California are of Mexican and Guatemalan origin or hybrids of these two subraces. ‘Hass' is a variety that has genetic origins of both of these subraces. Mexican origin typically have more cold tolerance than Guatemalan sources. Mexicans can often sustain cold down to the mid-20 deg F for a few hours when trees are mature. Young trees can sustain short periods under 30 deg but can be severely damaged or killed for prolonged times (more than 2 hours). Temperature and duration are not the only factors for determining damage potential. Humidity, wind and surrounding environments (proximity to open water, enclosed areas with reflective heat, etc.) are also important factors.

We know from experience that some varieites of Mexican origin are more cold tolerant than other varieites, some being able to the very low 20's for prolonged periods are survive. They may not produce fruit the following year because all the fruiting wood may be killed, but they will still come back. Varieties like ‘Bacon, ‘Zutano', ‘Stewart', ‘Susan' and even ‘Fuerte' are notable for their greater cold tolerance than ‘Hass'. They may not have the same eating and shipping qualities as ‘Hass' so they will not be commercialized on the scale that ‘Hass' has. But some people like these lower oil content fruit.

It recently came to my attention that there are some low chill avocado varieties that were selected in Texas where winter temperatures are usually killing for most of the avocado varieites we have have. Texas has a much smaller acreage of avocados than California and even Hawaii. So small (under 500 acres) that yields are not recorded for this crop. Most of the trees are backyard trees that have much more protected environments than a normal orchard setting. No really systematic data has been collected on their cold tolerance, but word-of-mouth has identified several varieties that might be cold tolerant. These are ‘Holland', 'Wilma', ‘Joey, ‘Fantastic', ‘Lila' and ‘Poncho'. They may not be the best tasting (that is in the opinion of the taster, as always), the best shipping (thin skinned and damage easily), or hang on the tree for a long period of time, but may make for a good backyard tree in colder environments.  There has been no systematic study to determine if and which of these varieties might be more cold tolerant that those that we already are growing in California.  Desperate gardeners might find them worth growing in marginal environments.

The avocado as an evergreen subtropical will never likely be a commercial tree in Canada (greenhouses?) but there may be more cold tolerance in the species than we normally associate with the crop. For a description of some of the characteristics of the Texas industry see the bulletin:  .

brogdon avocado
brogdon avocado

Posted on Monday, July 20, 2015 at 8:15 AM
Tags: avocado (278), California (12), cold tolerance (1), freeze damage (1), Persea (7), Texas (1), varieties (6)

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