Do HLB issues affect grafting and moving fruit in California?

Hey fruiting friends, any of you from California and knowledgeable about citrus? I tried posting these newbie questions on a more local gardening forum but it’s not as active as this one and I’ve gotten no answers:

I’m in Santa Cruz and I grow mostly pomes and stone fruits, but my family in the SF Bay Area wants to get rid of a couple of citrus trees in pots. Is there any problem with bringing them down to Santa Cruz? I heard something about not taking citrus from one county to another and I want to be super-careful.

Secondly, I’ve really enjoyed grafting with non-citrus fruits and would like to try to graft on these trees. If I bring them down here, can I graft onto them safely? At our CRFG scion exchange, they always say “no citrus!” so I wondered if there are regulations about or concerns with grafting citrus. What sources of citrus scions are considered safe? Thanks!

Yes, possibly. Not due to HLB as we do not have any confirmed cases of HLB in the state of Calif, save the one lone tree in Hacienda Heights that has been destroyed (infected graft to an existing tree). But, your family in the SF Bay area could possibly be in a quarantined county for the ACP, the vector insect for HLB, and if that’s the case, citrus cannot leave the county to go to another county. You can check by going to this web site:

http://www.cdfa.ca.gov/plant/pe/InteriorExclusion/acp_quarantine.html

And if you’re interested in grafting citrus, you need to use clean, certified budwood. You can order it for a nominal cost from the CCPP (Citrus Clonal Protection Program, part of UCR):

http://ccpp.ucr.edu/budwood/budwood.php

These would be the only truly “safe” citrus scions. I would never consider using anyone else’s cuttings. You just cannot be sure, and the CCPP is THE place to go for those of us in California. Good luck, and just ask any other question you might have about citrus. I am not very active any longer over on the GW Citrus Forum. Has sort of fallen apart. There is a nice citrus forum on the tropicalfruits.org forum, but don’t have a lot of time to spend on multiple forums these days. Plus, I really like this forum the best!

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Thanks much, Patty! Good info. I didn’t realize how complicated it was, but it looks like I can indeed bring the trees from Alameda County to Santa Cruz County. And I’ll do the budwood through CCPP.

I never intended to grow citrus because I’m sensitive to acid fruits, but I planted a Skagg’s Bonanza orange and a Meyer lemon that were gifts. I took good care of them but never expected to get Oranges in foggy Santa Cruz. I mostly just made sure they had enough acid fertilizer and zinc and iron to have nice dark green leaves, because I hate seeing the dusty, yellow-leafed, unpruned lemon trees that are all over town. Last year, though, the tree turned 5 and surprised me with a crop of DELICIOUS, not-too-acidic oranges! (I can eat them as long as I alternate with swigs of something alkaline.) This year it has set even more! Then after a tour and tasting at a local citrus collector’s property (Gene Lester, the “Citrus King”!) I realized I might be able to find some even lower-acid varieties to graft, but they’d have to do okay in the Northern California coastal environment. If any suggestions come to mind, please let me know!

I do have one question–my tree set way too many oranges and I didn’t want branches to break, so I’ve been thinning. Should I collect the ones I thinned and destroy them, or should I leave them under the tree to mulch back in? I don’t know if they are a hazard and will attract bugs, or if they are good nutrition.

Yeah, I like this forum better than the others too. This one seems to be the most active and friendly!
Thanks again!
Lizzy

Excellent, Lizzy! You don’t need “acid” fertilizer. Citrus are not considered “acid loving” plants, like blueberries, hydrangeas, azaleas, etc. Just good quality citrus fertilizer (one that is formulated for citrus, it is the N in the NPK that needs to be higher, and that is what will help green up your leaves). You should make sure the fertilizer has the full complement of micronutrients as well as the macros, not just iron and zinc. If you’re looking for a wonderful, high quality citrus that is low acid, there are several great options. Try Gold Nugget or Seedless Kishu mandarins. A great sub-acid orange is the Vaniglia Sanguigno acidless sweet orange. I happen to love them, but they are very sub-acid, so some folks don’t. Might be right up your alley. And yes, you should thin. Let the tree mature, branches thicken up so it can manage a heavy fruit load. If you’re thinning prior to maturity, either toss or compost. Do not leave them under the tree, they can attract pests, from bugs to funguses. And Gene Lester is a phenom. Be sure to take advantage of any tour to his place. He is a remarkable fellow and has probably the most extensive private citrus orchard in the world.