golden barrel in sw pa.outside.
golden barrel in sw pa.outside.
have 2 of these inside in a cool room by a window..what should the temps be befor i can put them outside ? rain isnt a problem becauce i have a big clear plastic storage container i can put over them..
like the farmer said to the tater,,i,ll plant ya now and i,ll dig ya later..
It'll be fine if it never goes below 37F again this spring. But I suspect it will. Best under glass at this time of year, they don't like sitting for days in cold damp conditions. They'll survive it but the skin tends to get marked.
You'll also need to stop it getting very wet, at least until it is really warm when it will appreciate loads of water.
You'll also need to stop it getting very wet, at least until it is really warm when it will appreciate loads of water.
--ian
Hi Clemons,
I have begun taking a few things out during the day. If it isn't going to be too cold (going down to 31 tonite, I leave them there (I'll leave them tonite).
But, it is going to be downright chilly this week coming up - lows around 20. I will bring everything in or cover them alot until next Thursday. Then, I think I am home free.
PA will take another few weeks before it is TOTALLY safe.
Alot of trial and error in this area....
I have begun taking a few things out during the day. If it isn't going to be too cold (going down to 31 tonite, I leave them there (I'll leave them tonite).
But, it is going to be downright chilly this week coming up - lows around 20. I will bring everything in or cover them alot until next Thursday. Then, I think I am home free.
PA will take another few weeks before it is TOTALLY safe.
Alot of trial and error in this area....
Tucson rarely goes below 20F, never(?) below 15F, but don't necessarily expect to match that hardiness in Pennsylvania. Low humidity, strong sun even in winter, and temperatures that warm up quickly from the nightly lows, all help cacti to survive the low temperatures. Also, planting in the ground provides extra protection to the roots vs being in a pot.
I've repeatedly had E. grusonii down to 25F in England, and had it stay right around freezing for days in a row. You should be able to match that easily, but don't do it with your prize show plants
I've repeatedly had E. grusonii down to 25F in England, and had it stay right around freezing for days in a row. You should be able to match that easily, but don't do it with your prize show plants
--ian
Hi Ian- The record low for Tucson was -13C (8F), December 28th, 1954. Man, I wonder what happened to the Sonoran plants there?
Anyway, water has a high specific heat and I think mucilage cells have an even higher specific heat, so I'd speculate that the heat gained by a plant such as E. grusonii and the surrounding soil during the sunny days in a place like Tucson makes a big difference overnight during frosts. This must be the reason that plants with a southern exposure backed by a reradiating wall survive hard frosts overnight when the same species not so situated will often turn into a pile of mush or be severely damaged.
Dry air is very important to certain cold hardy cacti as well. I'm not sure I understand the biophysics of that, but some hardy cacti do well to 10F (-12C) or lower only if atmospheric humidity is 30% or below and will be killed or badly damaged at higher humidity.
peterb
Anyway, water has a high specific heat and I think mucilage cells have an even higher specific heat, so I'd speculate that the heat gained by a plant such as E. grusonii and the surrounding soil during the sunny days in a place like Tucson makes a big difference overnight during frosts. This must be the reason that plants with a southern exposure backed by a reradiating wall survive hard frosts overnight when the same species not so situated will often turn into a pile of mush or be severely damaged.
Dry air is very important to certain cold hardy cacti as well. I'm not sure I understand the biophysics of that, but some hardy cacti do well to 10F (-12C) or lower only if atmospheric humidity is 30% or below and will be killed or badly damaged at higher humidity.
peterb
The basic physics of plant cell hardiness is that the concentration of dissolved salts and sugars in the water inside the plant must be raised so that the cells don't freeze. If ice forms inside the cells they will die. This is done by withdrawing some of the water from the cells, leaving behind the salts and sugars at increased concentration. Plants wrinkle, Opuntias lie down, Pediocactus shrink into inpenetrable spine balls.
High humidity and even condensation on plants below freezing can cause the surface cells to form ice crystals and die, while they would survived unfrozen in very dry conditions. Presumably humid air near open stomata is not a good thing
It is also easier to get plants in Tucson into a semi-dehydrated state where they can survive cold conditions better, than it is in England.
In many habitats (South Africa is a good example), plants are relatively short-lived and die in exceptionally hot, cold, dry, or wet years, to be replaced from seed in the soil. But I'm guessing this only applies to truly cataclysmic events with long-lived Sonoran cacti. Maybe 1954 killed some big old plants but I bet it didn't come close to killing them all.
High humidity and even condensation on plants below freezing can cause the surface cells to form ice crystals and die, while they would survived unfrozen in very dry conditions. Presumably humid air near open stomata is not a good thing
It is also easier to get plants in Tucson into a semi-dehydrated state where they can survive cold conditions better, than it is in England.
In many habitats (South Africa is a good example), plants are relatively short-lived and die in exceptionally hot, cold, dry, or wet years, to be replaced from seed in the soil. But I'm guessing this only applies to truly cataclysmic events with long-lived Sonoran cacti. Maybe 1954 killed some big old plants but I bet it didn't come close to killing them all.
--ian