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indoor Grow tent ventilation around the clock critical?

Hello,
 
Ponder a 60*60*140cm grow tent with a small fan blowing in at the ventilation hole and a 100mm inline fan sucking air from the top. The small fan is tied to a timer and the lights which means off around 8hrs during the night.
 
The inline fan was meant to operate 24/7..however, the tent happens to be located in my bedroom and this inline fan in this environment makes a "-...ooooooo" soun, from the exhaust side, that is hard to ignore at night. I got a sort of silencer, https://www.soliduct.se/fl-100-600-alu/p-2098.htm , which is nicer to handle than glass wooly piping but it doesn't help much with the droning noise.
 
I am okay with turning the inline fan off at night and keeping the tent flap open then (the cats aren't allowed in the bedroom), this means the one plant inside, a rocoto, would have passive ventilation in and out for 8hrs. Is this okay or severely detrimental to the health of the plant?
 
Thanks in advance for any insight. If this has been answered before a link to that would be swell.
 
 
 
I don't think it's critical .
I have use a medium sized grow box with only an internal ventilation fan on for maybe 3 out of 7 days a week or sometimes 6-8 hours a day.
Just check the effect on temperatures.
 
Thanks for your advice, will continue shutting it off at night and opening the tent flap (while the lights are out). (Ambient temps won't raise above 20C for the next six months or so)
 
 
 
Likely not a problem and under many circumstances it's unnecessary. I often run a fan on the plants and leave holes open or zipper cracked open.
 
Can you align the fan downtime with the lights being off?
How hot are your lights - HID; HOF; LED?
Big bushy plants in a small space need more ventilation than smaller starts.
Especially with bushy plants, are humidity levels an issue?
 
A fan in the unit zipped moving air around the plants and minimal passive ventilation may be as good or better than active in/out ventilation under certain circumstances, such when uncrowded and cold outside the tent.
 
Hey CaneDog,
 
That last sentence makes sense to me - for yes, humidity will be an issue, in that the levels will drop come winter. I plan to have a small humidifier running in the bedroom because else, from experience, the rh will be around 30-35%. I imagine the rocoto plant will become quite bushy but I've not grown one before so it remains uncertain.
 
In this tent the small inside fan is angled down (because it makes a racket otherwise). See http://thehotpepper.com/topic/69796-mini-indoor-revised/ , it's the tent with the sole inhabitant. Not pictured is the channel fan intake in the ceiling of the tent.
 
 
 
I grow a lot of rocotos, but mainly outdoors.  Indoors, I have rarely done more than over-winter them in a dormant state or had an extensive starting period prior to putting them out for the season to get them extra start time.  In my experience, they don't get bushy as much as they get big and leafy.  Air flow remains decent through the plant, but they take up space and getting light to the whole plant and avoiding stretch in the plant can be a challenge. They also seem to like a more diffused, cooler light versus a direct, hotter light which can exacerbate this.
 
For a fan, I prefer an oscillating one that sweeps through the plants periodically at a light to moderate force.  Plants will suffer from a constant direct stream of air, especially if it's strong. I'm trying to jostle them lightly with the air flow to build stem and branch strength (especially if they're eventually headed outside) and to avoid air stagnating within the plant, especially if they get bushy and start to retain excessive humidity from watering within the vegetation.
 
As far as the far getting drier in winter, being in an enclosed area the watering will increase humidity, especially if the air exchange with the outside room is limited. How you use interior versus exchange fans can help you increase or decrease the humidity.
 
Didn't mean to write a book here, but I just started my winter indoor grow about a month ago so thinking about many of the same things you are.  I hope you share pictures as things develop and best of luck!
 
 
 
I've had a 122 x 244 x 183cm tent for three or four years now.  
 
I run a large oscillating fan 24/7 to keep air moving (prevent damping off).
 
I keep a ducted inline fan on this temperature controller:
 
https://www.amazon.com/Inkbird-Max-1200W-Temperature-Controller-Greenhouse/dp/B01HXM5UAC/ref=sr_1_3?ie=UTF8&qid=1538239247&sr=8-3&keywords=grow+temperature+controller+inkbird
 
The primary reason I have it is to pull heat out of the tent and send it outside.  I suppose it also helps with air exchange / humidity.  
 
 
 
To answer your question :D I think you are fine turning it off at night as long as temp / humidity is stable.  I would suggest running a quieter oscillating fan if you can tolerate it.  I've had bad luck with damping off .  
 
 
 
Cheers for the additional input. Humidity inside the tents will be tricky as sub-zero temps outdoors will come and go, and when they do central heating makes sure dry lips, static discharges occur as well as an ambient rh at around 33% at 20C but then comes the rainy day and +9C outside and the need for ventilation in the tents increases. 
 
Hadn't heard about oscillating fans being better than fixed. For now I'll let the fixed ones be, off at night while rotating the plants a couple of times per week.
 
That seems like a neat controller NeedsWork, when temps are important. They will be when I insert the HPS light.
How does damping off appear?
 
You seem to have some experience of Rocoto plants Cane, thanks to your input I've moved the E27 "Italy 1957" marble desktop light (10W, 6000K) to one side of the Rocoto tent so that it has one Airam 10W mostly white LED (4000K) hanging from the ceiling and one 10W 6000K slightly more diffused from one side at knee height. I assume 6000K is an example of a cool light. Do these plants like it humid, like chinense? I'm equally non-aware in regards to the Baccatums..so far 40-50% rh seems fine, I imagine flowers not pre-terminating will be the crux.
 
 
chelicerae said:
Do these plants like it humid, like chinense? I'm equally non-aware in regards to the Baccatums..so far 40-50% rh seems fine, I imagine flowers not pre-terminating will be the crux.
 
 

I've never had an issue with humidity levels with rocotos myself (or Baccatums for that matter) though my conditions may be different than yours. I'd assume (pretty strongly, but without knowing) that they don't need the humidity levels of many of the Chinense given the climates in which many rocoto varieties grow.
 
My indoor grows usually involve more plants/density than what i see in your pictures, so I'll probably capture more humidity in the plant canopy or tent than you from watering.  Having just a couple/few plants in a tent probably won't capture as much. Even when I've started rocotos indoors for a few months without using a tent (just exposed to the dry house air) they've done great.
 
My other thought regards your lighting.  I could be wrong, but I doubt your tent is getting too hot with your lighting setup.  As NeedsWork commented above, a primary reason for the exhaust fan is to pull heat out of the tent and send it outside.  If you think you need more humidity and your temperature levels aren't requiring this, maybe run that fan even less - just a few hours per day - thus letting the humidity from watering and transpiration build up in the tent. As long as there's a fan moving the air inside you should be good. If you end up with a higher plant density in the tent you might need greater air exchange, but then again, that will capture more of the humidity from watering in the plant canopy.
 
Bottom line, I expect you won't have an issue with your humidity levels and plant health, but it's good to think about which levers you can pull if you do. I hope you'll continue to post pics as your indoor rocotos grow and produce.  I've still never done a full indoor life-cycle for rocotos and I'm excited to see yours prosper!
 
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