West coasters! Post up your Chill Hours!

Now that the winter chilling period is over for most of the west we can finally get a grasp on how we did. Post up your getchill (www.getchill.net) results and what state/zone you are in. Heres mine:

Outskirts of Phoenix Arizona 9a/b
Below 45 Model: 674 chill hours
Between 45 and 32 Model: 586 chill hours
Utah Model: 50 chill units
Positive Utah Model: 983 chill units
Dynamic Model: 17 chill portions

As you can see from the numbers we recieve a heavy amount of hours under 45 degrees BUT it really doesnt show in the Utah and Dynamic models because they discount our chill due to our temperatures swinging up into the 70’s often times on those same days that we see 8-10 hours below 45. This can really be seen in the Positive Utah model that doesnt discount for higher maximums and includes hours up to 50 or 55 degrees as chill. Its hard to know which model makes more sense for our unique area.

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25 miles outside of downtown los angeles.

Below 45 Model: 116 chill hours
Between 45 and 32 Model: 116 chill hours
Utah Model: -487 chill units
Positive Utah Model: 475 chill units
Dynamic Model: 12 chill portions

31.2 miles SE outside of Downtown Los Angeles

Below 45 Model: 88 chill hours
Between 45 and 32 Model: 88 chill hours
Utah Model: -595 chill units
Positive Utah Model: 487 chill units
Dynamic Model: 9 chill portions

My nearest station, KVNY, always returns zero in all categories. One less thing to worry about I guess. :clap:

Wow, you SoCal guys really got hammered on chill. On years like this are there varieties that dont fruit at all or is it just a case of reduced set?

This was a warm winter for us too. About the same as last year. A few years ago we were seeing about 1000 hours below 45 in my location.

Ah, my Davis weather station is not calculating my chill hours correctly. I have to get out and move it, so it is getting 100% full sun so the solar panel is getting enough charge. Tom warned me earlier, but I didn’t get it done for this next season. Will try to work on that this weekend. But, the closest station to me is showing this:

Vista, CA up in the hills almost 1,000 ft elevation, USDA 10b/Sunset 23
Below 45 Model: 227 chill hours
Between 45 and 32 Model: 213 chill hours
Utah Model: 7 chill units
Positive Utah Model: 765 chill units
Dynamic Model: 18 chill portions

Better than last year, but still not as good as previous years where I have been well over 300 ch’s.

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This data is from a park about a half mile away from my place at 33 feet elevation. Brady

Below 45 Model: 1371 chill hours
Between 45 and 32 Model: 1081 chill hours
Utah Model: 1681 chill units
Positive Utah Model: 1704 chill units
Dynamic Model: 72 chill portions

Don’t cry for me Arizona…My varieties are all low-chill and well suited for my locale, except for ‘Royal’ apricot which is marginal. More important for me is deep soaking rains, and we’ve had a few this year. :rainbow:

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Mine are too, Clint. I do have a few “pushers” I planted, just to see how they might perform. And yes, boy those rains will make a big difference. I did have some petal drop from the hail, but things look pretty decent, fortunately. And the best part - my Minnie Royal and Royal Lee are almost evenly flowering right now. So, here’s to hoping for a decent cherry crop this year. Will see how my other cherries fare as well, but these two cherry trees are the oldest in my yard (planted in January 2011 so now on their 4th year in the ground here.)

So far my Burgundy Plum and my Nectaplum are doing fine at breaking dormacy. My only worry is my flavor grenade which has yet, except for one branch with a couple of buds breaking.


Thats some beautiful chill, where are you located?

Does anyone know how things in the central valley shaped up? I hope they got a whole lot more chill than the LA basin did or they are gonna have a rough year. I recall the cherry growers doing alot of howling after the bad year last year.

I’m about 15 miles east of Seattle in Redmond,Washington.
I don’t want anymore chill now.Things are starting to bloom. Brady

Ahhh that explains it! Thats some seriously righteous chill man! 72 chill portions!! incredible. Thanks for sharing.

Do you get enough heat to ripen things like peaches to a decent sweetness?

Yes,mostly Nectarines,but I just put ten bare root,stone fruit trees in a hoop house in containers,a la fruitnut.
A young Flavor Grenade planted in the ground though,fruited for the first time last year(two pieces)but they were as good as any of that variety that I’ve had so far.
I’m still not up to speed on the meanings of the different models and right now go by the Between 45 and 32 category. Brady

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Here is a report from Modesto:

Below 45 Model: 148 chill hours
Between 45 and 32 Model: 148 chill hours
Utah Model: 353 chill units
Positive Utah Model: 502 chill units
Dynamic Model: 19 chill portions

One from Brentwood:

Below 45 Model: 443 chill hours
Between 45 and 32 Model: 412 chill hours
Utah Model: 745 chill units
Positive Utah Model: 1114 chill units
Dynamic Model: 47 chill portions

And one from near Andy Mariani’s orchard, for comparison:

Below 45 Model: 391 chill hours
Between 45 and 32 Model: 377 chill hours
Utah Model: 614 chill units
Positive Utah Model: 1030 chill units
Dynamic Model: 46 chill portions

I have been growing fruit for a long time I understand how many chill hours my fruit trees need. I am not sure what numbers count in the get chill numbers. Below,between,Utah Model,positive Utah Model or Dynamic Model. I have never seen them explained. Not sure of the numbers that count? Any help in this matter would help.


In your area below 45 is as good as anything. That’s what most nurseries use. Utah is for cold winter areas like Utah and high chill fruits.

Thanks now I know. No one has ever told me the answer. That means this year I had 1198 that is almost twice the normal chill of 600. Thanks agin