Heater settings

[sunfire]

Okay... so I don't have a greenhouse, I have a grow tent in an unheated garage. I am heating it using a small ceramic heater and a temperature controller that has day and night settings.

What temperature range do you set your greenhouse heaters at?

Right now I have mine sent to turn on at 65 and off at 75 in the day, trying to keep it averaging near 70 without cycling the heater too often. At night 55-65.

Is there any negative effect of the oscillating temperatures on the plants through the day, and if so at what extreme. Trying to balance this with not over cycling the heater.

I am also considering partially insulating the grow tent with styrofoam board as well. It already has a styrofoam hat,

[Roberta]

I set my GH heater at about 60 deg. F . Night temps fluctuate from about 60-68 (it's hard to keep a small greenhouse regulated tightly. It is actually pretty leaky, so some parts of it may be a bit cooler on the low side. The variation doesn't seem to be a problem, maybe even beneficial. (I don't grow species that need more warmth, like Phal violacea and bellina, or C. violacea. Other Phals seem to do fine. Daytime isn't a problem, it is is what it is. (I have turned off the fogger that I use for cooling in the summer) Day temps in fall/winter/spring get to be 75-80 deg F. ("Greenhouse effect). When it gets warmer in later spring, I'll un-mothball the fogger, that's my cooling source.

[Ray]

Set a minimum and that’s it.

Keep in mind that thermostats have setbacks, meaning that setting it at 50 degrees, for example, may allow the volume to get a few degrees cooler before turning the heat on. Pick the location where your coolest-growing plants are, place a thermometer there (preferably one that stores or records the temperature, in case you miss it) and use that as your baseline for adjusting the thermostat.

[Dusty Ol' Man]

A circulation fan in the tent will help even out the temps throughout the tent. In my large tent I have 4 fans running in different directions. The heater has a fan that runs while it is heating. My tent is also indoors. Temps are set to 85/65 day/night.

[sunfire]

Thanks all for your advice. My tent is small so I worry that leaving it set to one temp will have it clicking on and off too much. Funny thing is I got a smart thermostat/humidistat and more data means more questions, lol. Last year (with an even smaller tent) it was set it and forget it.

[dounoharm]

i grow cattleyas mostly, and i have grown them in all sorts of settings. right now, i have a little plastic gh that started life as a 10x7x7, a $69 special, lol after the first winter crammed on my porch, i moved it out to the jungle. (we recently moved to fla, but its a little far north, over by cedar key. so, the original gh got jacked up 2 cement blocks, and elongated by 12 feet. now its a workable size, not fancy, but effective. i use a little electric ceramic heater, and a big propane heater that sits on pilot. one oscillating fan.