Plan: 3 Ultimate Auto’s in 1 container. Too much?

[Pier]

Hi all,
I have a plan, but first I better describe the circumstances.

I have a rather cold attic. Temp is approximately around 15 degrees Celsius (60 degrees F).
I don’t have a grow tent. Lightning is a Mars Hydro TS1000. I grow on soil and feed with Plagron feedings.

The idea is to grow 3 Ultimate Auto’s in 1 container. The container can be 11 or 18 liter (3 gallons or 4,5 gallons).
The problem of the low temp I might solve by putting the container in an open electric heated propagator, so the roots and soil stay warm.

Can this be done?
- is 3 Ultimate Auto’s too much or not?
- what containersize I can use best?
- warming roots and soil: good idea or not? And if yes, what temperature is best for the soil and roots?

Please let me know what you think of this. Am I foolish to try this?

 

[Steppa]

Can I be the first to say it sounds like it's doomed to fail!.. sorry to be a bummer dude!
Plants don't like such cold temps... is that an average temp or daytime as it may drop further at night!..
Your light will lose effectiveness not being contained in a tent or cupboard etc..
Average plant pot sizes are 3-5 gallons for one decent plant!.. and there's the smell?!.. you may need to just chill a while have a read and think things thru a little better...
Other than that, good luck...
Easy now!..

 

[Arthur]

I take it your reference is to Dutch Passion AU. That's an XXL strain. 1 in a 3 gallon would be plenty, 1 in a five gallon would be better.

I figure 4 square feet per plant, but that's at normal temps. Keeping the soil temps up gets a big .

But...

You should look into some kind of enclosure, it will help with keeping the lighting & the heat where it needs to be. A tent would be best, set up with appropriate extraction.

Where I am, I don't have to worry about the smell, but that is definitely another concern to be addressed. An open grow can smell up the neighborhood if not checked. (Floral and fruit strains better here)

Environment plays a bigger part of a good run than most give credit too.

 

[Pier]

I appreciate very much your honest opinion.
Is the temp the only reason you think it will fail? I could wait till Spring...average temp will be around 70 degrees F.
Smell won’t be a problem there (big house, no neighbours in miles).

edit: yes, dutch passion AU.

 

[Arthur]

Temps are a big one.... when I started autos, I came over from photos and grew under hps. So i switched to LED at the same time.
I ran HPS temps the first couple runs (low 70s) and my plants were smaller than I expected (maybe 2 sq ft ea). Once I bumped that up to 80 to 84, growth blew up.
I think you'll avoid some issues by keeping the root zone warm, but don't know about all...

Personal experience from running autos outside, I start them indoor and don't move them to cooler temps till well established in veg, about 2 to 3 weeks. That's with 70s & 80s day, 50s nights. Those cool temps seem to just slow them down sizewise.