Chill Hour Calculator for California

Please excuse another California-centric post, but if you’re in the Golden State and like to geek out on keeping track of your chill hours here’s a handy tool bought to you by UC Davis: Cumulative Chilling Hours. Each year this page keeps track of chill hours between November 1 through end of February. If you know of a similar resource for other states/countries leave a link in the comments.

As cool (so to speak) as this tool is, what constitutes a chill hour and what kinds of fruit will grow in a particular climate is a complex question. For more on this debate see a provocative article on the Dave Wilson Nursery website, “Chill Out“.

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  1. Is there a book you’d recommend for pruning fruit trees? All I can find are books that discuss pruning from a landscaping perspective with maybe 20 pages set aside for fruit trees. Thank you.

  2. Hey Joss, I’d recommend taking a class or making friends with someone with fruit trees. It’s a skill that’s difficult to learn from a book. Where are you? If you’re here in California I might be able to find something for you.

  3. Fallbrook CA actually. Thank you! Also, what do you use to maintain your bike? I ordered some Orontas to try because it’s plant based instead of petro based and the 4 oz tub of “waterproof grease” looks so much like a balm I was wondering if bike stuff is possible to DIY.

  4. You’re actually in the best place in the known world to learn fruit tree pruining as Fallbrook is a hotbed of the California Rare Fruit Growers– I would go to one of their meetings–they have a very active chapter in North San Diego county. I’m sure you’ll meet someone who can advise you on pruning.

    Good question with the bike grease. I just have some petro based gunk. Will have to research that.

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