Anyone who grows tropical plants in Florida has seen wind chill damage. I saw a bench of orchids that got blasted by a cold front years ago down in Homestead, Florida. From the south side, the plants looked fine. As you walked around the bench and viewed from the north they were brown and scorched. The plants had gone unprotected from a north wind that moved through overnight.
Nice shots of Clyde's place, by the way.
My theory is that the wind is dessicating, not actually "chilling", because I was always taught that to experiance wind chill, the animal had to perspire... I know that plants transpirate, but I think that may be different... I could be totally off basis, but I am just hypothisizing(sp?). Since plants to not actually sweat to cool off, I think that the wind just dessicates them, because it removes the moisture from their leaves, hence the "blow-torched" look... Sorry if I have a lot of mis-spellings right now, the room is FREEZING and my fingers are numb... Ciao!
I am back..
I think your theory is probably right-wind chill for humans would be a different factor than for plants. All I want to do is warn Florida based Nep growers, who most likely grow their plants outside, to protect them from the wind even if the temperature is not that cold.
Any time there is evaporation, there is cooling, so windchill effects happen to plants too. Wind on nepenthes then would not only dry them out, there would be cooling as well.
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Hence the phenominon windburn.
Nepenthes - hail to royalty
Also, for those of you with N. coccinea, it is the most prone to damage because of the thin leaves. It will tolerate a drop to 50 F if there is no air movement other than the convection currents caused by a heater. The ventrata (Belgian alata) takes the cold snaps much better.
Since your plants are already adjusted to outdoor conditions, I wouldn't worry too much. Yes, in winter you can get lower light levels, but also the temps get lower. I've found that my neps outdoors adjust to winter conditions pretty well. I do grow primarily highlanders. My temps range from low 40's and occasional upper 30's (rare) at nighttime without any problems. I experience no frost so the leaves are pretty much undamaged. If you have true lowlanders, then you might want to move them indoors on those cold evenings. For example, N. bicalcarata doesn't like low outdoor conditions. I've been able to slide by with N. rafflesiana and N. ampullaria outdoors without problems. N. truncata appears to be a brute too. However, I introduced them to outdoor conditions this summer, so they're doing alright with the light, humidity, and temp changes.
In winter, I raise my shade cloth and provide my Neps with more direct sunlight. Some plants have had some leaf browning at first, but then the subsequent growth is fine. Only a cosmetic setback. Almost all of the others could care less and go about their merry way. Species with papery leaves like N. mirabilis, N. ampullaria, N. hirsuta don't take higher light levels and drier humidity as well as others. So check for that "waxy" leaf coat. That protects Neps from windy or less humid conditions. Maybe you can find a place where your Neps get morning sun and afternoon shade to offset the high light levels.
Other than that, if you're not sure, bring them indoors where it's safer until you can find a more "appropriate" place so you don't loose any valuable Neps from your collection. You can always experiment with ventricosas, alatas, and maximas to see where the optimum growing conditions are at your place without sacrificing the rarer guys.