1997 blueberry trial - northern highbush in low chill Santa Clara

I was recently told that @applenut has successfully grown a couple northern highbush blueberry cultivars in Southern California. I was browsing on the internet and found that thanks to some Santa Clara master gardeners, it has been known for nearly 25 years that northern highbush cultivars (typically rated high chill) will fruit in the low chill environment of Santa Clara.

I thought I would share the links for those interested:

Has anyone else already done this? BTW, thank you @applenut and SCV master gardeners, for testing these things out for us.

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Santa Clara county is Northern California, where San Jose is,

The difference between northern and southern CA is the difference between a redwood forest and a cactus desert.

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Here is the post of successful fruiting of a northern highbush cultivar in inland southern California:

As mentioned, that’s actually Northern California so it’s a little higher chill than you probably think.

That said, there is something weird about California in general that allows plants to grow there that you would think don’t get enough chill.

I’m guessing it’s because of cool nights compared to places in the humid southeast that otherwise have similar average temps, but I’ve never totally understood it.

Um, last time I checked, @applenut was indeed located in Southern California. Have I missed something? (Yes, I do realize that Santa Clara is in Northern California - like me - but that doesn’t appear to be relevant to Kevin’s experience.)

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Yea - correct. Sorry, I was focused on the Santa Clara aspect.

Just to clarify - I did not cite the Santa Clara study because I was confused about geography. I cited it because Applenut’s findings were surprising and worth attempting to understand. The difference in climates does not matter for the question we are asking. We are not asking which is the better location to push chill limits on NHB cultivars. I am aware that Santa Clara can grow things I can’t. That isn’t the question. The question is whether the northern highbush chill ratings of 800-1000 are true or false.

Applenut said they are false (at least for him, at least for that one year). Is he right or wrong? So we look to see if anyone else has proven those chill ratings false. The only other place I found where this was tested at all was the study I attached.

Here is a sample excerpt from the Santa Clara Master Gardeners, linked above:
“Said to require 800 chilling hours for proper dormancy, but has been a very high yielder every year even though chilling hours have fallen to less than 300.” - Santa Clara master gardener’s description of Earliblue (Vaccinium Corymbosum = northern highbush)

That is some serious myth busting if true! This forum is about learning and doing things better and sometimes trying things that have not been tried before. Sounds like in both locations that worked out - the growers ended up eating good fruit, with the added delight of overcoming pessimistic conventional understandings.

NHB varieties may have wider adaptation than we realized. I would encourage people to read the links and form their own conclusions. They are short. There was another myth busted in the article, one that might be more important for those growing at home.

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OK, blueberry update:

  1. KaBluey was excellent here in Southern California, fruited just fine.
  2. Last summer’s 117F heat wave killed KaBluey to the ground, along with a bunch of Magnolia street trees, and the top 3 feet of our avocado tree. Apple trees took it in stride, just a few singed leaves.
  3. Survivors of the blueberry massacre were Brightwell and Emerald.

If blueberry plants die in high heat, it is almost always a result of not having enough water. This is one reason I am considering irrigation for my blueberry plants. I have a spring with a pump. All it would take is about 50 feet of 1/2 inch pvc pipe and some irrigation tubing along the rows of blueberries.

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Hi Kevin,

Did you try any other northern highbush varieties and have them fail to fruit?

What was the season like for the northern (NHB) varieties? For me for SHB Emerald, and most other SHB varieties, I get enough blueberries for cereal in late April and then the whole month of May I get tons of them, and then by June the plant is (I presume) depleted and the berries are not as intensely flavored, and I tend to move on to raspberries and apricots by early June. I saw in one post you said that Ka-Bluey extended the season on the early side one year? That totally surprised me. I would have expected them to be later. Thanks.

Here is legacy, a northern highbush cultivar, fruiting April 30, a year after planting. For some reason last year Amazon/Wholefoods was selling northern highbush cultivars in southern California. They must have read of Applenut’s experiences… Just kidding. Whether accident or not, it looks like you can get at least some northern highbush blueberries in at least some lower chill areas of California. One thing I like about this plant is it is a lot more vigorous growing than my SHB cultivars. If I knew which ones were earliest here, I would put in a trial patch of more NHB cultivars.

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