I first wanted to say thank you everyone for your patience during my “writing absences” and for your continued prayers for healing. I’m hopeful that over the next few months I’ll be able to get back to a normal blog post schedule as I continue to make slow but steady progress with my health.
The cool weather is definitely here! It’s been fairly cold in the Las Vegas, Nevada area with daytime highs in the mid-high 60’s and nighttime temps hovering around the mid-high 40’s. When you’re used to warm weather, this can feel bone chilling cold.
With the onset of colder weather, our fruit orchard responds by winding down for the season and preparing for winter slumber. The visual clues to the start of this process are a few “crunchy” leaves on the trees with a few scattered about on the ground for good measure. The “big leaf drop” should take place before the end of December.
Late Fall also typically starts the “chill hour” countdown in the orchard. This year is right on schedule – we’ve already had several nights with temps below 45°F (see note on chill hour temperature range below) . If you’re wondering what chill hours are, I’ve included some info below as well as a link if you want to read up on it a bit more. There are several great sources of info out there – but my “go to” source is Dave Wilson Nursery. They are the leader in the fruit tree business and produce high quality fruit trees. All of my fruit trees are from Dave Wilson.
Chill hours are…
“The amount of chill needed to satisfy a trees dormant rest requirement, plus the amount of heat required to initiate growth, determines how long buds will remain dormant. In general, the lower the chill requirement, the earlier a tree will bloom.”
Most (if not all) fruit trees require a specific number of chill hours. Living in a desert area with mild winters like I do, I’ve selected fruit trees with low chill requirements (less than 500 chill hours; some less than 100 chill hours). Now if you live in an area with extremely cold winters, you would be better off with trees with higher chill hours. With low chill varieties, you would run the risk of meeting your tree’s chill requirement too soon. As a result, your fruit tree could break dormancy early and bloom too early, leaving it vulnerable to the cold weather. Bottom-line… you could lose your blooms to the cold and have no fruit that season. Yikes! Make sure you plant fruit trees with the proper number of required chill hours for your area.
Chill Hour Temperature Range
There are several “chill hour models” people follow regarding how you count the number of chill hours. Personally, I follow the simplest model (see below) and stay away from “tracking” actual chill hour numbers. I just like to check on-line weather sites periodically and monitor upcoming weather reports. My trees have such low chill requirements that I’m confident when the weather is cold, the chill hours will be met during the season. I’d show more concern if our Fall/Winter season was unusually warm or cold and would probably pay more attention. Even at that… the weather’s gonna do what it’s gonna do! Getting around it is a moot point. As a responsible home orchardist, stay informed and care for your fruit trees and orchard as best you can and let mother nature do the rest.
every hour below 45°F = 1 chill hour;
temps below 32°F do not count toward accumulated number of chill hours
In preparation for seasonal frosts, hubby ordered a couple of frost blankets for our baby citrus trees: Meyer Lemon and Algerian Tangerine (Mandarin). The blankets should be arriving soon. I’ll pass along a few tips when we set things up.
It’s been nice chattin’ with you dear ole friends. Hope you have a wonderful day and weekend! This Saturday, Hubby and I are headed to the farm for some fresh organic veggies 🙂