San Luis Obispo County
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New Crops – Rumpa or Rumba or Copao or Copado or Eulychnia brevifolia

Growers are looking for alternative crops and drought tolerant ones are better than water intensive ones, right? So, here's a recent question from someone who wants to grow the latest, new food crop.  “What about growing a drought tolerant (in fact, it doesn't need any water) cactus fruit that will make money?”  Cool. 

My first response is that it should do no harm. That should be a mantra when it comes to food, especially in this age of hyper-food safety vigilance. People are clever, though and foods that might be dangerous are often produced so that they can be eaten by most people. We do have acorns with tannic acid that need to be leached if you don't want to get severely sick.  Olives that need to be processed to edible. Puffer fish that with a wrong slice of the knife can kill you. There are any number of other foods that people have figured out a way to safely eat. 

Rumpa is cactus fruit from Chile that has a lot going for it – high nutrient content, high polyphenolic antioxidants, high C, small seeds like kiwi and pitahaya, and tada, drought resistant for our drought prone state. So, it's a cactus, yeah, but it doesn't have the teeth crunching seeds of opuntia cactus fruit – the tunas or prickly pear – that can scare some people.  Too vigorous chomping on the wondrously flavored prickly pear fruit leads to the small, hard seeds.  Shocking, although they are safe to swallow, mostly.

There are spines, but the fine spines on the rumpa fruit surface can be removed by rubbing on an abrasive surface. Not too vigorously, though since the fruit is quite delicate. This would be the same for the tuna fruit, too.  You can get rid of those spines with rubbing, too. So, eating the rumpa should be relatively safe.

The safety issue pops up with the spines on the stems. They are wicked thorns that protect the fruit with all the defenses needed to protect fruit in a hostile environment.  This is going to be a tough fruit to harvest.  Which may add to it glamour, like puffer fish.  Although in this case, it's not the consumer who is taking the risk, but the harvester.

Or you could grow dragon fruit, which is a cactus relative, which has no spines on the fruit and a few on the modified stem/leaves. It's got entirely edible, beautiful seeds. The right variety of dragon fruit can be quite tasteful, although many are quite bland.

So back to the question posed by the grower. If it's safe to eat, do you want to grow it?

According to Francisco Meza in the link below (google translation):

“Its fruits, called rumbas, have a bitter taste similar to lemon, but less tart, which would prevent them from being consumed fresh. However, thanks to its nutritional qualities, such as a high content of vitamin C, and good flavor once sweetened, could be used in the processing of processed foods such as jams, juices and drinks. But that's not all, since according to experts it can also be used in the manufacture of cosmetics.”

So, the advantage California coastal ag has is its climate. That's the competitive advantage.  If it can be grown cheaper, processed and shipped here from somewhere else, it's not going to work competitively here.  It's hard enough competing with similar climates like Mexico's and Chile's where the shipping becomes a problem for perishables.  But that is being dealt with and it's becoming hard for out-of-season coastal blueberry growers to compete with imported fruit in the season that the coast has dominated for the last several years.

So grow rumba/rumpa/copao in Ventura commercially? It's safe to eat.  But it doesn't sound like something that you gotta have….now.  It sounds like it needs to be jazzed up, which means processing. It's hard to pick.  And the market needs to be developed.  So, it's probably not a good idea to grow it commercially on the coast.

Posted on Tuesday, November 21, 2017 at 7:06 AM

Psyllid News Along the California Coast

              Task Force ACP-HLB update

HLB update

To date, 232 residential citrus trees in Southern California have tested positive for the HLB bacterium. All have been, or are being, removed. Most were in neighborhoods in LA and Orange counties. Three of the trees were in Riverside, and although they were residential trees, the resulting 5-mile radius quarantine for HLB is affecting a few growers in Riverside and San Bernardino counties. 

The latest HLB quarantine map with the running tally of HLB detections in the state can be found at the Citrus Insider website: The maps are updated every week.

Tree removal

As HLB detections increase and spread closer to commercial citrus, it is a good time to consider removing any citrus trees that are unloved, uncared for, or not worth the time and resources required to protect them from ACP and HLB. Untreated citrus can serve as a reservoir for ACP and possibly the disease HLB, increasing the risk to other citrus in the area. The Citrus Matters ACT NOW program may be able to assist with tree removal at little or no charge to you. Find more information at: Or if you need referrals for tree removal services, contact Sandra or Cressida.

ACP-HLB program meetings

The California Citrus Pest & Disease Prevention Committee (CPDPC) is made up of growers and other representatives of the citrus industry, working with the California Department of Agriculture (CDFA) and others. The CPDPC is funded in large part by grower assessments and steers the statewide effort to protect our citrus from ACP and HLB. The full committee meets every other month, with subcommittees meeting in between. All committee and subcommittee meetings are public and open to anyone to attend or listen remotely via computer or phone. Agendas for upcoming meetings and minutes from previous meetings are posted on the CDFA website:

Coastal citrus representative needed for CPDPC

There is an opening for a grower representative from the coast to serve on the CPDPC. Be a part of deciding how grower funds are spent to protect our industry. Details can be found here:

Santa Paula crew boss workshop

On Wednesday, Nov. 29, the Citrus Pest & Disease Prevention Program and California Citrus Mutual are hosting a free train-the-trainer workshop in Santa Paula. This Spanish-only workshop for crew bosses, ranch managers, etc., focuses on preventing human-aided spread of ACP and HLB. It has been approved by the Department of Pesticide Regulation for 2 hours of continuing education in the "other" category.  For details see:


Feel free to contact your ACP-HLB grower liaisons if you have any questions or need assistance:

Cressida Silvers

(805) 284-3310


Sandra Zwaal

(949) 636-7089

Posted on Friday, November 17, 2017 at 5:55 AM

Central Valley Avocado Meeting


 Interested in San Joaquin Valley Avocados?

 When:  NOVEMBER 28, Tuesday, 1PM


UC Lindcove Research and Extension Center Conference Room (22963 Carson Ave, Exeter, CA 93221), Central Valley.


Tentative Program:

Welcome and Introductions – Mary Lu Arpaia, UC Riverside

Challenges to growing avocados in the Valley

Irrigation, Fertilization and Soil Requirements – Ben Faber, UCCE, Ventura County

Avocado Root Rot and how to manage – Greg Douhan, UCCE, Tulare County

What is the California Avocado Commission and the Hass Avocado Board? – Tim Spann, California Avocado Commission, Irvine, CA

Results from the Tier 3 varietal evaluation block at UC Lindcove REC – Mary Lu Arpaia and Eric Focht, UC Riverside

Ideas for the Valley Avocado Industry – Group Discussion


Walkthrough of the Tier 3 varietal evaluation block



RSVP to Diana Nix (

For more information contact Mary Lu Arpaia (


Posted on Wednesday, November 15, 2017 at 6:08 AM

Berry Meeting for Coastal Subtropical Growers


You are invited to the

North American Raspberry & Blackberry Conference

February 21-24, 2018 • Ventura, California




Wednesday, February 21: Opening Reception

Thursday February 22: Full-day Bus Tour of Farms and Research


Friday, February 23 and Saturday, February 24: Educational Sessions, Posters, and Trade Show.


Session topics include


SWD management • Mite control • Raspberry pollination


Organic/biological pest & disease management options

Frost tolerance of blackberry buds • White drupelet disorder

Temperature management in tunnels • Spray application in high tunnels

Primocane blackberry pruning • Water and nutrient management

Calcium nutrition in raspberries • Tissue testing to optimize fertilizer programs

Caneberries in Mexico • Berry promotion • Consumer and industry trends

Night harvesting of blackberries • Post-harvest & packaging • Food safety for caneberry growers

Berry breeders & nurseries panel • Pest control advisors panel • Growers labor issues panel


English–Spanish translation will be provided


Location: Ventura Beach Marriott

Only a block from the beach. Special conference rate is $149/night. Call 805-643-6000 and mention "Raspberry & Blackberry Conference" or make reservations online at Cutoff date is February 1.

For more information and registration

Or contact the North American & Raspberry Blackberry Association at or 919-542-4037


Exhibitor inquiries welcome.


This conference is being held by the North American Raspberry & Blackberry Association in cooperation with UCCE


Posted on Monday, November 13, 2017 at 6:09 AM

Bees to Look Out For

Nearly 1600 species of native bees can be found in California's rich ecosystems; this colorful pocket-sized card set will help you identify 24 of the most common bees found in urban gardens and landscapes.

Using this card set, you'll be able to identify bees on the wing to the genus level. Included for each featured bee are color photographs, a general description of appearance, the distribution and richness, flight season, nesting habits, floral hosts, and how each transports pollen.

Also included is a brief description and illustration of the anatomy of a bee, a glossary, bibliography, and online resources so you can delve deeper into the lives of these fascinating social insects.

Designed as a companion to the book California Bees and Blooms. This 3-1/2" x 5-1/4" card set is spiral bound and printed on sturdy laminated paper to hold up to rough service in the field.

CB & B also has lists of plants attractive to different bee species


Get this and "California Bees and Blooms" at :

Posted on Thursday, November 9, 2017 at 4:35 PM

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