1st grow, California Desert heat, second story grow enclosure: Questions

Howdy gang! I've been lurking for a while, took the plunge and signed up!
I have lots of time available to give to my grow, either with the plants or reading to learn and educate myself.

I've got a first time small indoor grow going on. I started out with 26 bag seeds and now am down to 3 and a clone I bought. The bag seeds are part of my learning curve and I really don't care if they produce much as they are sacrificial of sorts all in the name of my education. I gave most of them away and destroyed the males. I would much rather make mistakes with the BS's than with the seed bank seeds I bought.

4 plants in a 3ft H x 2ft D x 4.5ft W enclosure made from "science fair" type cardboard with Panda plastic on it. (can be made taller, up to 5 feet).
I started out with a 4ft x 4 T8 light fluorescent fixture from the hardware store and upgraded to a High Output T5 4ft x 6 bulb fluorescent fixture.
The enclosure is not 100% sealed, the room the enclosure is in is 99.5% light proof. (able to seal off room reasonable well) There are also a couple of small fans and seem to just be circulating air in the enclosure. I prop open the top to let fresh air in. I'm using an Exhale bag and made a sugar/yeast CO2 bottle but have read that that's just a waste as the fluorescents don't produce enough light for the extra CO2 to be beneficial.

The room the grow is in is an upstairs bathroom. The one wall and window is west facing. I've hooked up the bathroom exhaust fan with a 3inch dryer type tube going into the enclosure and it exits up through the second story vent pipe on the top of the house.
Fresh air comes from the adjoining room or through the bathroom window.
I didn't really have a heat problem with the 4x4 T8 lights but now do with the 4x6 T5's.

The problem I'm having is now with the light upgrade, and summer in the California Desert fast approaching, is keeping the grow enclosure under 95 degrees during the heat of the day ( swamp cooler will be up and running in the next two weeks). The swamp cooler is downstairs and cools the upstairs only a few degrees.
My thought to correct this heat problem is to change my 12/12 currently from 7AM-7PM to 9PM-9AM to avoid lighting during the hottest part of the day.

My questions:
1: Will my nicely flowering plants get messed by abruptly changing the light start/end times?
2: Will the fresh air from the opening of the window pollenate my flowers?
3: Supplemented CO2, waste or beneficial?

Feel free too give input!
I will post pictures tomorrow for you all to critique my work.

Hi and welcome!

i'm in the same boat here, NM desert and its getting hot. hit 86 today. in my experience, swamp coolers just dont cut it, especially when temps get over 95. and since my grow area is more humid than the rest of the house, its not clear that swamp cooler (which works by adding humidity to the room) would work at all for me. so i'm planning to do the same thing you are, switching to lighting during the cooler part of the day. i'm a bit luckier than you, in that i haven't started fruiting yet, so i can do the time change when i switch over.

I don't really know how to make a switch like yours. do you leave the lights on for 24 hours? my first instinct would be to keep the room dark for 24 hours. I mean, in nature, there a days when its cloudy or darker than usual. and i think leaving the light on for 24 would have more of an affect on the plants hormones, but i'm just guessing here.

hopefully someone else will know

1: Yes, do not mess with your photoperiod once it has been established. It can cause herms.
2: It could happen if there are male pollen spores floating around but its probably unlikely. The problem with having the window open would be bugs, dirt, etc. You could use a screen and that would help with the bugs but not the dust.
3: Deploy CO2 and you will not only increase your yields but you can safely go up to 95 degrees with the light on. You will have to use about 2000 or maybe even up to 2500 PPM of CO2 at 95 degrees but it could be cheaper than A/C.

i know nothing about CO2.. i read something early on that said don't bother with CO2...that it makes your leaves greener but doesnt help yield at all. but now it looks like its time to learn.

Co2 rocks, but it's not something you throw at a high heat sitation as a solution. co2 will benefit a properly tuned CEA "sealed" system and it can allow yo to run at higher temps. But those temps have to be controlled and consistant. Humidity need so be controlled as well.

If your in NM at least your in the hi desert with some cool nights. Run you lights at night. Many people will shut down during the heat of the summer. If you want to do year round, go sealed with a controlled environment.

yeah i think next year we'll just plan to shut down during summer. but for this year, when i move my plants to fruiting i''ll run 9pm to 9am. should save some money running more on an off=peak schedule anyway. i feel bad for RudeKitty. seems she has fewer options than i do, since she's already on 12/12.

Thanks for the input!
I was thinking of gradually rolling back one hour each day until the 12/12 7am/7pm was to 9pm/9am.
Will that work without freaking out the ladies?

Howdy there. Another california high desert grower here. Do not switch the light schedules on them. It stresses them out, slows them down, and youre running the risk of hermying. Chances of pollination from fresh air are low since you're indoors. I wouldnt worry too much. Supplement with co2? Yes! From my experience it will boost your yields up to thirty percent if everything else goes right.

Okay first off keep the lights off for 24 hours if you want to switch them. I have done it dozens of times and never had a hermie induced by that even in week 8 of flowering. Second don't bother with that bullshit CO2 rig. Consistency in CO2 is a lot better than the spikes and drops of that. Plants can become addicted to C02 and if you run out of yeast or for whatever reason stop using it, it will stunt your growth a lot, in some cases it will even stop growing entirely.

berkman858 said:

3: Deploy CO2 and you will not only increase your yields but you can safely go up to 95 degrees with the light on. You will have to use about 2000 or maybe even up to 2500 PPM of CO2 at 95 degrees but it could be cheaper than A/C.

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No truth in this statement at all. Co2 will give you maybe 7 or 8 degress more to work with, so 82-83 MAX! There is no amount of co2 that lets your temps go to 95 safely.

without AC, you're going to have a lot of problems during the summer.

You can switch your light cycle for sure. Just add an extended dark period instead of an extended light period. Always best to run your lights at night, IMHO. Helps balance temps better.
CO2 could possibly help, but it's going to cost you some money to set up a decent system.


I know you don't want to hear this, but your best bet is to save indoor for seasons when you can get temps under control... Your yields and quality will be a lot better during winter/fall.



Go scout some outdoor places where you can plant a clone.

Thanks all you cool cats for the input!
As this is my learning curve and I'm not too concerned with yield for this first round, I count this as major mistake #1 for me.
Note to self, for my growing conditions, plant in early fall! I've got a few seeds to plant then, JTR, Vortex and Pandoras Box.

Clown Baby said:

without AC, you're going to have a lot of problems during the summer.
I know you don't want to hear this, but your best bet is to save indoor for seasons when you can get temps under control... Your yields and quality will be a lot better during winter.

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