Chill hours

Once again it is December, it is cold for a California boy (I think it’s supposed to be 60 tonight), my fruit trees are losing their leaves, and therefore it’s time again to consider chill hours. There is a calculator for California at https://ucanr.edu/chillcalc/index.cfm?controller=station&action=index And it is fun to play with. Still, it is my guess that we have no clue about the actual biological systems that give us a tree setting bloom or not. Certainly cool/cold temperatures are required and yet…. My cherry trees have bloomed every year since I put them in and there is no freaking way we are getting 400 chill hours. 2 years ago I had a tomato plant survive the entire winter and then produce tomatoes in the spring within 20 feet of the cherry … which bloomed and had a good crop of cherries for the squirrels and birds :-) I seriously doubt that a tomato plant can survive 400 chill hours. The funny thing is that my 100 chill hour apples have the toughest time resetting for spring. I would bet that there are several systems that overlap and allow the tree to sense ground temperature, light conditions, air temperature, etc. The cherry and tomato were near my pond and it’s possible that the pond kept the air temperature warm enough for the tomato but the ground temperature got cold enough to reset the cherry. Who knows, my point is that if you have a fruit tree that you want to plant, don’t worry so much about the chill hours required. Plant it, water it, nurture it, and see. Bob 310 429 8477 http://www.PuraVidaAquatic.com