ok, Winter is approaching slowly here in east Texas. I don't know how cold it's going to be but usually it never really get's too bad here. But cacti are a bit more sensitive to cold therefore I bought a small greenhouse, 7x7 feet all directions.
My question is this: how much humidity will I encounter ( actually my plants)? The greenhouse has 8 vents and 2 doors. Do I need to leave the vents open, even if I put a heater in the greenhouse for when it gets cold or colder? I don't want to add extra humidity. I'm a bit confused as you can tell because I never had a greenhouse!
Ah, the world of cacti.....I think I need a drink!
It would help to know what your greenhouse panels are made of, single wall vs. double. My area the temps can get down to 25 degrees and at times even colder. If the temps are going to drop below 25 degrees I might heat it for those cold temps. As it is, I don't heat and the past two years the cactus did fine. I have 8mm double wall polycarbnate panels.
Opening the vents would defeat the purpose of the heater. At the very least it would cause the heater to run a lot more than it would otherwise. What kind of heater are you going to use? If you use a heater that works off of combustion (like Kerosene) then you need ventilation. If you use electric heat then no vent is required. As for humidity, I doubt it will be a problem. Winter air is dry to begin with and heating dry air will make it dryer. I guess if if feels dank and muggy you may need to air things out a bit, but don't forget that your plants survive summer in east Texas. That's pretty darn humid!
I'm now selling plants on Ebay. Check it out! Kyle's Plants
I don't think you will have a problem with humidity. My greenhouse is made of 6 mil polyethylene "greenhouse film". I heat with heat lamps on most cool nights and a propane heater during the coldest. I keep my greenhouse closed during winter and don't have a problem with humidity. During parts of fall and winter, condensation forms inside the plastic, but I have never had any issues resulting from it. As stated before, if it is combustion (I.E. Propane) you will need some ventilation. Even though I leave my greenhouse closed during the winter it is nowhere near air tight. Air can still circulate a little. My propane heater has a carbon monoxide sensor in it so it will shut off any builds up, but it never has.
hmm I will be in the process eventually of making an old portable garage (designed to hang tarps) as a greenhouse. I was wondering about all this stuff, a few mental notes taken.
Here's to you, all you insidious creatures of green..er I mean cacti.
Peter, my new greenhouse is portable, 6.5x8', made out of gore-tex, rip proof, 100% waterproof, and it's bigger than I thought it would be. It really looks nice. We had a storm here last night with high winds and lots of rain and this morning everything was like I left it before. It has 2 doors and 4 vents and also 4 small bottom openings for a hose and electrical cords. It also comes with a shadecover! I can walk around in there even with 2 fairly large metal racks on each side for all my plants. There is actually a middle aisle! Since I am in Texas and 40 degrees is winter here I could not see a huge investment in a brick and mortar greenhouse. The nice part of this greenhouse is that I can buy another one and zip them together if I ever needed more room. So far I have 60 or so cacti and they all fit in there nicely with lots of room to add more! Which I will do of course. One can never have enough of them!
I will post a pic as soon as I upload one of the greenhouse.
Thanks, Susie! No, we don't get gale-force winds here, and if a tornado ever shows up here everything starts flying, including the brick house. Fortunately that hasn't happend here in the 40 years I have lived here. Besides that, whatever happens, happens. Right now my little greenhouse serves me well, and I'm hoping it holds up for awhile! At least I haven't spent a ton of money and work on it.
nice greenhouse, it's great to live in weather conditions that make that possible!
With apologies to the late Professor C. D. Darlington the following misquotation springs to
mind ‘cactus taxonomy is the pursuit of the impossible by the incompetent’ - Fearn & Pearcy, Rebutia (1981)
sundanz wrote:Thanks, Susie! No, we don't get gale-force winds here, and if a tornado ever shows up here everything starts flying, including the brick house.Karin
And I think I would rather be hit by that than a brick house or even a glass gh.
Susi
Humidity, or at least it condensing out, depends on how different the inside temperature of the greenhouse is to outside temperature, so the higher you heat it proportionately the more condensation you will get on the greenhouse structure. Unless you are growing very tender tropical cacti frost free or a few degrees above freezing on coldest nights in winter is usually good enough when they should be dry and in a resting state anyway. Other succulents that grow in winter can be more difficult, but I will leave them to those who grow them to advise. No point in using more heat than you need anyway.
nice greenhouse, I have been very busy lately including working on the greenhouse/hothouse/growhouse for my ex's mom. She has MS so I have to do most of the stuff for her
Here's to you, all you insidious creatures of green..er I mean cacti.
