One paper below found Orangered required 1266 chill units as per dynamic model (UC Davis may give those hrs). That was the most of 10 cultivars studied. My results in the greenhouse would rate it as needing the most chilling of anything I have Robada probably being next most.

Orangered bloomed poorly, ~5%, at ~600-800 Utah hrs in 11 and 12 but started to break bud before I finished this year at 1270 Utah.

I think part of my issue in 2011 and 12 was that I jumped into 16 hrs per day chilling Nov 1 and the trees may not have been ready to accept chilling at that point. This year in addition to running a month later I gave the trees until Nov 22 to start chilling.

I'd say Orangered is a poor candidate in Vista. If you can chill it you aren't really a low chill area, a possibility I guess. But I've been following your weather some and the last month looks more like summer than winter to me. Maybe you have a cooler microclimate than weather.com shows.

Here is a link that might be useful: apricot chilling requirement

This post was edited by fruitnut on Sun, Feb 2, 14 at 16:31

Oh gosh, definitely. Twice what I could provide it without artificial methods. And yes, I am cooler than the 92084 weather.com will show. I actually have my own Davis Instruments weather station, and can track my CH's with Tom's wonderful "Get Chill Hours" algorithm (thanks for your clever site, Tom). Tom, who is also in San Diego county, and further east than me doesn't get as many chill hours as I do at nearly 1,000 above sea level. We have a very, very specific microclimate where I am in the hills of a coastal valley. We are surrounded by orchards and commercial nurseries, as everyone who grows anything commercial wants to be where I am :-) If you have a wunderground.com weather station near you, or, have your own station and it's registered with wunderground.com (like mine is), you can use Tom's tool to get a much better approximation of your CH's.

Patty S.

Here is a link that might be useful: Get Chill Hours!

Patty,

I'm up in Modesto and bought an OrangeRed and a Robada this year. My area is marginal for the OrangeRed but I figured it couldn't hurt to try.

I didn't have Fowler's current home-growers catalog at the time and didn't know they were offering Nicole or I'd have bought that, too. David Karp rated its fruit pretty high.

I can't find the chilling requirments for it but it was developed in Parlier, so probably Central California normal.

UC Davis tabulates chill hours for many California stations. Takes all of the work out of it. See the link below.

Chose your station from the list and on the next page you can select start and end dates. It also shows historical data.

gary

Here is a link that might be useful: UC Davis chill calculator

Thanks, Gary. I have my own weather station on my own property actually :) due to our extreme variance in our particular area, I opted to install my own which broadcasts data to wunderground.com. So, I am able to compile my own data both with my own software, as well as with the data feeds to wunderground.com. So, much more accurate data. There is a Davis reporting station on Twin Oaks Valley Rd. that is reasonably similar, so I can use that data for years 5 and great if I need to. Apricots are the fussiest of all the stone fruits, with cherries a close second for me. So, we'll see how all my marginal varieties fare this year, as this is year 3 and 4 for many cultivars in my orchard.

Patty S.

That was an interesting paper that Dr. Coville wrote that fruitnut pointed to.In it,he indicated that dormancy sets in before cold weather and it,cold weather,is not necessary for complete dormancy,although cold is very important for various reasons.
What is the trigger for a plant to start to go dormant,as it's not covered in that short paper?Is it something that's already built into them?
On the Get Chill site,what is ideal date to start with,when the temperature reaches 45F?Also,if only choosing one of those three models,which should I go by? Thanks,Brady

This post was edited by Bradybb on Mon, Feb 3, 14 at 10:49

Patty,
I'm not sure if grafting is an option,but Bob Purvis has OrangeRed scion material.I may give it a try. Brady

Well, I think my CH's are simply insufficient for this cultivar, so probably not worth the time trying to graft into one of my trees. Let me know how you do, though.

Patty S.