So I just recently harvested the fruits of my labor and was dissappointed. Out of my 3 indica bagseed plant's that I started back in January, I just harvested about 2 weeks ago I had a total harvest weight after dried and cured of 2 OZ's. I am using a 250 Watt HPS (from start to finish) 3 gallon planters with Scotts Premium soil mix + 1/3 part perlite. I only fertilized once during veg which was approx 21 days long using time release (big mistake) and fertilized about 4-5 times during flowering using MG 15-30-15 @ 1/4-1/2 stength. I stopped using fertz around week 6 being naive thinking that my laides would be done by that time. I harvested some at week 7, that was clearly not done (good amount of white pisitls about 60% and trichs were 80% clear 20% milky and harvested the rest at 9 weeks when trichs were 95% cloudy and 5% amber). I watered as needed being careful to not overwater. Now here is where I believe my real problem is: My temps in the begining were in the mid 70's to low 80's and began to get hotter half way through flowering. Around week 7 I noticed all growth had come to a crawl, and my temps began getting higher averaging 80-85 lights out and 88 (min)- 90 (avg) 95 (max) lights on. Water was used up very quickly, having to water every 2 days until harvest. The problem is I really can't a/c this room since it will become obvious I am doing something in there. The room is made out of concrete from top to bottom, so when its cold (which is only 2 weeks a year) is stays pretty cool and temps aren't a problem, but this isn't practical since winter is premature in my neck of the wood, so for the most part it is hot as balls during the summer. Here is my question (sorry for the whole case study) if I were to add a time release CO2 system increasing levels to 1500 PPM, would this help counter the high temps and generate a substantial increase in growth and yield. It sucks when I go to tend to my ladies because I begin to sweat until i'm soaked because of the high temps. I'm not complaining about that, but about my yield. If I were to get 250 grams per harvest out of 4 plants in 3 gallon square planters using my 250 Watt HPS with the addition of the expensive ass CO2 system ($300) I would be satisfied. (currently have 4 plants 1 K-train, 1 LSD, 1 Purple Lady, 1 Gigabuds from 12/12). Also could that amount of 1500 PPM be hazardous to myhealth as the air in my room tends to recirculate and isn't really vented directly outside the room. There are a good amount of cracks and openings so I know I won't suffocate and the plants get a good amount of air, but I'm trying to really do this growing stuff right but need to be stealthy as well. Also are my nute's and soil garbage and should I just switch to foxfarm for soil and nutes? My harvest has a rather average smell, not like when you see a 10/10 bag of kush that you can smell from 20 ft away. My buddy rated my harvest a 7/10 which was dissappoiting to here after all my work lol. How do i grow that incredible High Times looking/smelling 10 out of 10 weed? Was that just a product of it being bagseed or did I neglect something??? HELPPP!!!
250 grams per plant under 250 watts hps is not ever going to happen. when u goto look at ur trichs before harvesting you want half amber and half cloudy...there are too many factors that i dont know about that could have contributed to youre small yield.
I am well aware of the 50/50 cloudy amber/mix for a good harvest (my preference being 95% amber due to my love for the couchlock), in case you didn't notice I wrote experts growers please help, not amateurs. I might as well troubleshoot and figure it out myself through trial and error based on your advice. Where the fuck is Dr. Greenthumb when you need him instead of Nurse Greenthumb....
You are going to need to address your temperature problems. Get a Portable A/C that will operate completely in-room. Adding CO2 to a 90+ atmosphere won't help much. 85 is as high as you want to go. 1500PPM CO2 won't endanger you at all. Getting Fox Farm's can really only help you. Also more light = more bud.
The heat is probably one of your minor problems, but higher temps can be tolerated with decent results. I think the biggest issue you had was lack of good nutes. A veg cycle of 21 days is pretty short, and in order to have more bud you have to have branches for them to develop on. I would suggest a longer veg cycle, and more nutes during veg. One possible help to your heat issue is to run your 12 off cycle during the day. That way the 12 on is running during the night (coolest part of the day). It can help some. A good intake drawing fresh air in and an exhaust pulling hot air out is vital. I wouldn't worry about adding CO2, in a small set-up its not cost-effective. You had a successful grow, be proud of your results. They will get better with experience.
Yet again TexarkanaTim provide me with sensible and useful answers. I had my setup running during the night to try and counteract the problem, however there was no big decrease in temp by doing this so I just switched backed to doing it during the daytime. Basically my temp in my room is the temp outdoors. I think you are right with respect to the nutes and the short veg cycle being the 2 factors that limited my yield. I will work on those 2 issues on my next grow, right now my set up of 1 K-train, 1 LSD, Purple Lady and Gigabuds have been under 12/12 from seed and all are showing pistils. I had a issue with my lamp and had to replace the bulb, and was lucky enough to find it at home depot. I will post some pictures so you can give me some feedback. +rep (if it lets me rep you again)
I tried the portable A/C however it actually increase my temps by 5-7 degrees instead of lowering it, so normally without A/C my temp get to 90 Max, with the A/C the hit 95-98! That's why the A/C wasn't practical in my case.