Hi Jim at what temp will this heater keep your GH in 6b?

Same question for you Chip, I still can't believe your temps, about 7 years ago we went down to -17f for three nights, killed half our trees and plants that was brutal but -40 my my my

Sorry Daisy missed your post while I was typing , Is Reno water as alkaline as mine? ours here is off the chart, and we don't get enough rain [5-6"ayear] to collect so I have to live with what I have, I'm on a well. Is that a problem for orchids?

Our city water is between 8 and 8.5 (no wells). My orchids don't mind and as the pH is due to alkali, not minerals, my misters don't clog . We were on a well in California - my misters were clogged once a week! The orchids didn't mind although their leaves were always water stained because of the minerals.

Last year, we got 2.55 inches of rain. So far this year .7 inches.

The dry end of my greenhouse is full of cactus.

I use a 1500W milkhouse heater. It turns off if bumped and I put it on a milk crate to keep it farther from the floor and potential damp. I've used a radiant dish heater, but I always worried about it setting something on fire.

I have a whole slew of fans to keep the air moving, and an aquaponics system that provides a certain amount of thermal mass but the the heater is set to turn on at about 40F. The inside of the greenhouse still gets regular frosts and the occasional hard freeze (especially against the windows) but I try and choose plants hardy through zone 9 and its usually not a problem. (I have cymbidiums, citrus trees, tea plants, amaryllis, and some azaleas in there year round.)

binfordw said:I was wondering about using propane, kerosene, diesel, etc. I wondered if the fumes could have a negative impact on plants, I'd hate to use one in a pinch and kill everything I had started.


I was mainly thinking about a kerosene/diesel "salamander" style heater.

African Violets are sensitive to gas and paint fumes. There are stories of people finding a fainting violet and being warned of a potentially dangerous leak.
i am not certain about carbon monoxide effect on plants. My grandfather died when a shed door blew shut. He didn't notice and the fumes from the generator in the shed killed him.
Might buy a Canary. Birds will keel over from carbon monoxide before humans do.
It is not anything to joke about or take chances with. Several people died in Texas trying to heat their homes with car exhaust during the storm down there.

wiltshire said:Hi Jim at what temp will this heater keep your GH?

Same question for you Chip, I still can't believe your temps, about 7 years ago we went down to -17f for three nights, killed half our trees and plants that was brutal but -40 my my my

-40° is uncommon– p'raps one or two nights every third winter. The other night it was -26° and -30° is not unusual.

My winter heat is first from a solar collector and a 50% glycol loop of PEX tubing, with coils through a 400 gal heatsink (a stock water tank) under the floor. It's driven by a small DC pump on a 20W solar panel, so it's pumped when there's sun to heat the collector. Basically, automated. The water in the heatsink can get up to 120°F, but at 80°F I start an AC Taco pump (for fishponds, fountains, etc.) to push warm water through a maze of PEX tubing buried in the insulated floor, 12Lx12Wx3D, which is the main thermal mass. I try to maintain it at 50-55°F. Outside, the ground temps go way below freezing.

There are four large black water tanks on a southfacing wall, which get up to 65°F on a sunny day and radiate about 8-10° at night. The electric radiant lamps kick in at 45°F. I light the propane heater at about 0° to -5°, when an electric power outage would kill a good many plants during the night.

Given the severity of our local climate, having several means of storing heat is wise. In ten years, some tomato plants have died from cold air leaks through the louver vents, but otherwise it's worked out. I posted more details and photos in this thread: The thread "Please share photos of your greenhouse" in Greenhouses forum.

wiltshire said:


Hi Jim at what temp will this heater keep your GH in 6b?

Same question for you Chip, I still can't believe your temps, about 7 years ago we went down to -17f for three nights, killed half our trees and plants that was brutal but -40 my my my

I was growing all cold weather plants, so my goal was to keep it just above freezing on the coldest night. I would set it to come on in the mid-30's and shut off at around 40.

subarctic said:We live in a remote spot and there are frequent power outages, so the propane heater is my backup. It's hooked up with a hose to a portable tank outside.

I run it on the LOW setting, except when the power's out, when I set it to HIGH. My greenhouse has enough air leakage that there's never been a problem with it shutting down.

I have that same exact propane heater and I love it. Just a heads up, when it's set to high it'll go through one of those little propane tanks. I was using it on low for over a month, and finally I gave in and spent the money on a connector hose, a bigger tank, and then getting it filled. I primarily use it while I'm smoking on the back porch (terrible I know), but I also used it in my greenhouse until I got the wick changed on my dad's old kerosene heater, and now I use it. The best thing about that little propane heater is the fact that you can use it inside and it turns off if there's low oxygen.

And, here I am freezing my butt off smoking on my front porch all winter!