How to care for Sarracenia in freezing weather
Feb 24, 2022 16:57:43 GMT -5
stevebooth, rmeyer, and 9 more like this
Post by meizzwang on Feb 24, 2022 16:57:43 GMT -5
SARRACENIA WINTER CARE
Sarracenia in the wild somewhat recently took down to 5F in the deep South during a polar vortex, so they can take some seriously cold weather! However, in cultivation, you may need to protect them under certain circumstances. How do you manage your Sarracenia collection when the temperatures are predicted to go to 32F (0C) or below? It depends on a lot of things! After you've finished panicking, the most logical thing to do is to realize that you shouldn't worry too much unless it's FREEZE YA BOOTY COLD! What temperature range is that? Keep reading.
First, let's discuss the range of threshold temperatures that matter to us. For those of you who are real scientists baffled by Mike Wang's quasi-terminology, please note that I'm making up these words and defining the temperature ranges specifically for Sarracenia:
1) light freeze: 27F-32F (0 to -2.9-ish)
2) moderate freeze: 20F-26F (-6.7 to -3C-ish)
3) Freeze ya Booty cold (this is the technical scientific term. Some call it Butt you know what-ing cold, but I'm keeping this thread PG-13 for as long as possible): below 20F (-6.7C)
Things to factor in besides the actual temperature itself:
1) can cold air move underneath the pot? Are you growing on a porch where air can move below the plants, or on tables where air can move beneath the plants? If so, this greatly increases vulnerability to freezing temperatures.
2) are your plants in a small pot? A large pot? The larger the volume of soil, the greater the buffering capacity to temperature and better tolerance to cold.
3) is your grow area an open field, exposed to all the elements, or is there some small level of protection from wind and cold? Protected areas, such as near a house, near a solid cement wall, or near a large mass of material that can absorb/radiate heat may allow your plants to tolerate lower air temperatures.
4) Are your plants in a bog with a large volume of soil/water, and are they fully established/acclimated to the environment? This will greatly increase their cold tolerance. Conversely, are your plants recent divisions or new acquisitions that were greenhouse grown? This can diminish their cold tolerance.
5) Is there snow? This will insulate from the cold and provide a barrier against wind chill.
6) How long did the freezing event occur and at what temperature? The longer it's really cold, the greater the threat to the plants.
7) IS it windy during the freezing cold temperatures? This will increase vulnerability to the cold
8) level of hydration: water has a very high heat capacity, so the more water you have in the substrate, the more protected the plant is.
9) temperature during the day before the freeze: if the soil warmed up a lot before it freezes at night, this can help increase tolerance to cold air. Conversely, if it's freezing during the day and night, this will lower the plants' tolerance.
10) are your plants on top of gravel? Soil? Cement? whatever they're sitting on will affect their cold tolerance.
This preliminary list will hopefully get you to start thinking about other factors in your specific grow area that can either increase or decrease your plants' tolerance to freezing temperatures.
LIGHT FREEZE
During a light freeze 27F-32F (0 to -2.9-ish), keep the soil well hydrated. If you didn't, it probably won't matter, especially if the air is still and the grow area has some protection (ie. near a building). If the plants are covered in snow, you're all good, snow will insulate them and keep them from the extremes. If you have new divisions that aren't yet fully established, it's probably safer to protect them (eg. bring them inside or in a frost free area) until the threat of cold weather has passed. Some small seedlings can perish if they're not strong enough or hardened off enough, so protect those too! If you have plants that were weak or new acquisitions that were greenhouse grown/not well grown the previous season, as they say in the Caribbean, "protect ya Tings, MON!" Bring them indoors or place them by the side of the house or structure. You can cover them with thick black plastic, remay, thick layer of pine needles+snow, or a frost blanket. If there's new growth and you don't want to lose it, bring them inside.
Moderate Freeze
During a moderate freeze (20F-26F or approx. -6.7 to -3C), things can get a little dicey, but for the most part, if the air is still and all of your plants are fully acclimated/established in your environment, just make sure everything is kept fully hydrated. Dry and cold is a big threat, and so is freezing and thawing. Duration is also something to watch out for: If it gets to 20F at night and then 75F during the day, and repeat this for 1-2 weeks, some plants might get jacked up by the cold if not protected. Also, if you have a week of freezing cold nights in the moderate freezing temperature range versus months on end in the moderate freezing temperature range, that makes a huge difference!
At the soil level, my $1.99+tax thermometer read 20F (I know it's accurate because 4 other different brands of thermometers read the exact same temperature when stored in the same room). The weather report said it was going to be 28F at the lowest, so keep in mind that your microclimate may be significantly different and that predictions are just educated guesses. Also, I believe they are talking about air temperature, but we also care about the temperature of the soil! There were zero Loses from this freezing event, even on thousands of recently divided Sarracenia:
Sarracenia growing in an unprotected, open field that is exposed to all elements. When this picture was taken, the temperature at soil level was 20F. The peat was rock solid like pavement, I couldn't push down on it with my hands:
Any new growth that's more than 1/2" tall will likely die off in 20-26F weather. Buds still in the rhizome survived:
A row of Sarracenia flava right when the sun came up. an hour earlier, the leaves were covered in frost and the soil temperature was 24F. The soil was still frozen when this picture was taken. Not a single plant perished despite zero protection, including hundreds of recently made, new divisions:
S. psittacina with an ice mowhawk:
Frozen purpurea row. Again, ZERO casualties at 20F:
slightly off topic, but I'm sure some are wondering. Flytraps can take 20F too if fully acclimated:
FREEZE YA BOOTY COLD
Now when it comes to freeze ya booty cold weather ( below 20F or -6.7C ), I don't personally have any experience with this, but here's a culmination of information that I've put together after getting feedback from many other growers who are in more Northern climates (including one of our own SF forum growers here, Rick Meyer aka rmeyer):
1) Fully established plants in semi-protected areas can survive some temperatures below 20F under specific microclimates without protection.
2) S. rosea, S. psittacina, and S. minors seem to be more freeze sensitive than other species. That said, they can definitely survive below 20F temperatures when protected, and when unprotected under specific weather events (eg. under snow, still air, in a semi-protected environment). In a large bog, all of the species, if fully acclimated and established, can survive some very cold temperatures unprotected.
3) S. purpurea ssp. purpurea was the only species that survived unprotected up to 6F potted. Other potted species perished when unprotected.
4) Covering up plants and placing them by the side of a heated structure provides significantly more protection in comparison to an unheated structure, like a detached toolshed.
5) You have to be very careful about rot when keeping dormant plants indoors in an unheated garage.
6) some growers opt to put all of their plants in large bogs outdoors. Leaves are left untrimmed during the dormancy period and are cut off once the threat of deep freezing has passed. They cover the plants with a thick layer of pine needles, and then let a thick layer of snow cover the plants on top of that. For months, the plants sit under the pine needles and snow, even during extreme freezing events, and are very well protected. All of the species can survive this method, including psittacina and rosea. The toughest challenge is figuring out when to take off the pine needles: too early and they can get jacked up by a cold weather event. Too late and the warm weather can potentially cause rot issues. Ideally, once the temperatures are estimated to be above 25F, as long as there's no freeze/thaw/wind-chill factor, you should consider taking off the protective pine needles.
7) Some growers cover all their potted plants with thick black plastic or remay until the threat of extreme freezing weather passes.
8) new divisions, even super strong ones from Mike Wang, may perish if exposed to this weather, so don't risk it!
For those of you in Freeze ya booty cold weather, feel free to add your experience to this thread!