Chiling hour question

[Texan]

I am just not understanding the chilling hours thing. I found this definition but I still dont get it

The chilling requirement of a fruit is the minimum period of cold weather after which a fruit-bearing tree will blossom. It is often expressed in chill hours, which can be calculated in different ways, all of which essentially involve adding up the total amount of time in a winter spent at certain temperatures.[1][2]

Biologically, the chilling requirement is a way of ensuring that vernalization happens.

Could somebody make that easy to understand? Please.

 

[bid]

Using peaches as an example, the tree goes dormant in the fall. Temperatures at or below 45 degrees satisfy the chill requirement of that particular variety. So if it needs say 800 hours, after those 800 hours have been met the tree will come out of dormancy as soon as the weather is warm enough and begin putting on new growth and begin to flower. If the hours are not met the tree will not flower uniformly or set fruit uniformly. The problem commercial growers have at this time of the year in some areas is that the chill requirement has been met and trees come out of dormancy but are susceptible to late freezes killing blossoms or small fruits.

Does that help?

 

[setter4]

Hey! This just reminded me that I put peach pits in the fridge last fall. Guess I need to find those. lol I'll let the GD plant them and see what we get!

 

[Texan]

Using peaches as an example, the tree goes dormant in the fall. Temperatures at or below 45 degrees satisfy the chill requirement of that particular variety. So if it needs say 800 hours, after those 800 hours have been met the tree will come out of dormancy as soon as the weather is warm enough and begin putting on new growth and begin to flower. If the hours are not met the tree will not flower uniformly or set fruit uniformly. The problem commercial growers have at this time of the year in some areas is that the chill requirement has been met and trees come out of dormancy but are susceptible to late freezes killing blossoms or small fruits.

Does that help?

Yes, it does. Thats fairly simple. I just for some reason could not get that. Thank You.

 

[patandchickens]

It's the same thing as heating or cooling degree-days (as would apply to your home heating or airconditioning needs, respectively), only expressed in hours of course

Pat