24 Hours of Chill

Utah chill hours i.e. Over the next four days. I love this kind of weather, as long as there are no hard freezes. Hopefully, this year my high chill Flavor Supreme will bear fruit!


I call that today in Pennsylvania. :smiley:

Low of 32, high of 43. Warm compared to last week!

I have a cold room where I overwinter containerized trees. I sometimes take them out and wake them up early for a little extra growth under lights indoors. But when should I wake them up? Utah chill hour model and Acurite to the rescue! I bought an Acurite smart hub and put a sensor in my cold room (as well as outdoors and in my growing room) to monitor the temperature and humidity. The smart hub intercepts sensor data and reports the value to the Acurite server every 10 minutes. You can create an account on the server, register your hub, and look at charts of your data. You can also create alerts for you phone if temperature or humidity hits a trigger level you set. One more feature is to download a CSV file with your sensor data.

I wrote an excel macro to ingest the CSV file and calculate the chill hours my trees have received. I just type in the date the tree when dormant and into cold storage and the number of chill hours to date based on the Utah model are displayed! It is a great little tool. My cold room is significantly warmer than the outdoor temperatures so actual chill hours can vary a lot from outdoors.


I will get 3 or 4 days like that and then the temperatures will be in the 70’s for a week. It really confuses the plants. I have some young blueberry plants blooming and winter really hasn’t even started. Usually there will be enough remaining buds to give a decent crop the following spring. I also have some volunteer tomato plants that are still growing.