Carnivorous Plants/Winter Care
QUESTION: Hi Jeff, while this is not a concern yet. Upcoming I hope to move to a cooler place in AZ. Payson is the area I'd go and the elevation is from 5100 to 6000 feet. My question is about winter care. In the video you talk about covering plants for protection from freezing winds and to protect from repeated freezing and thawing. My concern is, while I think I got the covering from wind down, the freezing and thawing has me wondering. Example is, the temps will be in the upper 40's to 50's during the day and drop to 25ish at night for about 5-6 hours. This is usually after midnight. So, should I cove the plants each night even IF there is no wind? Is that what you meant from freezing and thawing?
ANSWER: Hi Jason,
The mountainous areas in Arizona sound very much like our high desert in Central Oregon, but probably not quite as cold. You may need to consider having them in some kind of a cold frame that can be ventilated during the day, or consider overwintering them someplace like a garage once they are fully dormant. If 25 was the coldest it got you would be fine, but I'm guessing it can get much colder than that.
If you have them in a garage, clip the leaves for the winter and spray them with sulfur fungicide to prevent mold.
Now having said all this, if 25 is truly the average cold temperature, that's really no worse than here in Oregon, so you could just leave the out. Just make sure they have plenty of water. We sometimes get clear spells that are just like this, and the plants have ice in trays in the morning, it melts, then it freezes again the next night. You may just have to watch them to see how they do and decide if they need more protection.
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QUESTION: Thanks Jeff, Payson is at 5100 feet so winter time lows are mostly in the 20 range each night but the days rebound into the 40-50's. So they would be freezing and thawing somewhat each day. That would be my main concern. Down here in Phoenix I have had the lows that way and even colder but it's certainly not for 3 to 4 months each night. I wonder if after they have gone dormant it would be good to cover them with frost cloth and a tarp each night. Of course I'm speaking of them being up there. Here is no big deal at all.
Here's the thing I would watch for. See if the soil is thawing all the way during the day, or if some ice seems to be remaining. What you don't want to have happen is for the soil to freeze while the tops of the plants are transpirating and can't draw up water. If they thaw all the way during the day, you are probably fine. Covering them at night certainly won't hurt, and it will retain some ground heat. Cutting off all the leaves during the winter really helps too.