Temperature and growing

[Jackalope]

Now that winter is approaching it is time to talk temp. I forget what the book says is perfect temp. Pretty sure it is around 72 to 85 f. The reason I don't know those numbers is because I have always grew with what I had. What they are supposed to have fell by the waist side soon after I started growing.

That's what I wanted to talk about. You can grow pot in lots of different temps. How fast they grow and how well they will produce might be effected. Still they will grow. For years with out air cooled lights. My temps ran from 50 to 90 degrees f. Last year with the air cooled lights and a move to a different spot. My temps ran between 60 and 75. I harvested enough bud to supply myself both times. I really thought last year was going to be better. They grew great. Didn't produce worth a shit. That was caused by the lower temps I am sure. Because growth was slowed they didn't use the normal amount of nutrients. Because of that I ended up with weed that wasn't flushed very well. Gets you high fine just doesn't burn well.

My temps now, in the new house are running in the 70's and 80's. The growth rate is amazing. So fast it almost created a problem LOL. It is going to be real interesting to see if temperature was the main reason that I was not getting better production rates like I have been expecting. I kind of hit a wall with production rates lately. They went to a certain level and then leveled off. I should be able to grow better.

With all that said. My point is not on production. You get what you get. Temp is the main subject. They will grow in damn near any temp within reason. While it is great to get perfect temps lots of people can't get perfect. That is the reason for this thread. I want people to know they can still grow in less than perfect temps fine. I know plant growth slows after 90 f not sure where that number is on the low side but my guess is it is around 60 f. As long as you stay away from too long at those temps you are not going to have any problems.

Where problems arise is when we try and control things to much. Once you try adjusting temps to a better levels you are leaving yourself open to other problems. I have had lots of times where the solution was worse than the problem to begin with. I am hopping to hear more about temps from others. What people have grown in with success. Plus temps where things went to shit. Along with those I hope for solutions that they used. I am fine with everything I am doing. I just thought this would be a good time to get info to those that do have temp problems. Even the fact that it is winter time I am sure there are a few with high temps.

With so many little tricks out there it is a good time to share them. The fact that growers have to use what they have and are on a budget. There should be some really interesting idea's.

 

[Herby Paisley]

Hi Jackalope...Good thread to start!.... Well when it comes to temps I'm getting my last outdoor/shed grow to harvest in about a week and half its on a DWC system, In ontario Canada and my plants are doing good even seeded them too, My temps have been between 68F during the day and 52F at night with a few nights lower then that the growth may have slowed a lil bit but the ladies are still packing on the buds and seeds and trichomes are becoming more amber So I would say cold temp growing is very do able..I may try to push the limits with an experimental grow in the shed over winter and see how cold those plants will take it till they start dying.

 

[Remystemple]

in veg i'll let the temps get pretty high. in flower i try my hardest to keep the max at 82f.

 

[Dusted]

I just lowered the temp in my room by 2-3 C by changing the location of my circulation fan. I noticed the current grow had slight wilting of the large fan leaves at 28 C. This is an indica grow and they perked right up when I got the temp down to 25 C. Instead of just internally circulating the air I now blow cool basement air in the bottom of the doorway and exhaust out the top.

 

[Remystemple]

I should have added that i keep a heater in my tent so lights off temps don't go below 72. it seems like i'm having a lot more growth, bigger buds from it. idk if that's it tho.

 

[Jackalope]

Hi Jackalope...Good thread to start!.... Well when it comes to temps I'm getting my last outdoor/shed grow to harvest in about a week and half its on a DWC system, In ontario Canada and my plants are doing good even seeded them too, My temps have been between 68F during the day and 52F at night with a few nights lower then that the growth may have slowed a lil bit but the ladies are still packing on the buds and seeds and trichomes are becoming more amber So I would say cold temp growing is very do able..I may try to push the limits with an experimental grow in the shed over winter and see how cold those plants will take it till they start dying.

Some strains are going to do better than others in the cold. I am starting to take more notice to things like that when looking at strains. Now that I can grow in the temps I have. I need to optimize it.

A couple years back I had to transfer plants to a new place. It was cold. Way cold, around -12. I only had to walk 60 feet or so and thought they would be fine. Just that 20 or 30 seconds it to me to cover that distance. I had leaf damage to the plants. That kind of surprised me. I am curious how much cold they can stand and still bud ok.

 

[Jackalope]

I know the lower temp range created problems for me. Or a combination of high and low temps. When I had the Powdery Mildew problems. I was giving it the perfect environment to survive in. Days above 80f and nights around 50f. I was paying high enough power bills I have never added a heater for warmth.

I ended up moving the whole grow to a different place and got a air cooled fixture for my light. That is when I ended up with temps in the 60's and 70's. I got rid of the temps that P.M. thrived in and that seemed to help. It took lots of treatments and cleaning to get rid of the P.M. It is gone for now at least.

 

[AdaminCO]

This is the chart I’ve been using in regards to Temperature and Humidity.
I run 75-80F (78F) in the day, 70-75 (68F) at night. I read that the plants do well will a 10F change from day to night.

Someone on here pointed out that you need to read the temp off the leaves, but I figure in about 3 degrees +\-. I don’t have a laser temp. gauge.

0C620228-3FC4-4CC2-BB1B-0AE0747582CC.png

• AdaminCO
• Aug 21, 2019

Vpd

and another to cross reference for flower.

 

[Remystemple]

This is the chart I’ve been using in regards to Temperature and Humidity.
I run 75-80F (78F) in the day, 70-75 (68F) at night. I read that the plants do well will a 10F change from day to night.

Someone on here pointed out that you need to read the temp off the leaves, but I figure in about 3 degrees +\-. I don’t have a laser temp. gauge.

0C620228-3FC4-4CC2-BB1B-0AE0747582CC.png

• AdaminCO
• Aug 21, 2019

Vpd

and another to cross reference for flower.

these charts are good, but it's definitely not easy to keep it within these ranges without some equipment. i've learned to not stress too much about it as long as both rt and rh are within acceptable ranges. if something is way off I'll worry about it tho.

my veg tent has been getting down to 40% rh and they're fine. i was worried for a bit based on the charts but not anymore.

 

[AdaminCO]

these charts are good, but it's definitely not easy to keep it within these ranges without some equipment. i've learned to not stress too much about it as long as both rt and rh are within acceptable ranges. if something is way off I'll worry about it tho.

my veg tent has been getting down to 40% rh and they're fine. i was worried for a bit based on the charts but not anymore.

Yeah, same here. It’s always a good base reference. Hell my clones are sitting on a window sill in the basement and they’re 3.5’ tall now. Lol!

It’s 65-70F and 45-55RH and they love it. I try to think in terms of a 10 point difference between the two and regardless I’m good.

 

[Vegan4life]

I live on the coast and Humidity is often between 70% - 80%, I run dehumidifier which causes heat, run AC to combat heat, it gets expensive, I cut my air exchange back in grow room to couple of minutes twice a day, to save energy. Try to keep temp in room between 75 - 80 degrees F and humidity between 50% - 60% during flower. I'm going to raise temps to 80 F - 85 F and humidity to 60% - 70% on next grow and see how that works. I believe air movement is also very important.

 

[Remystemple]

I live on the coast and Humidity is often between 70% - 80%, I run dehumidifier which causes heat, run AC to combat heat, it gets expensive, I cut my air exchange back in grow room to couple of minutes twice a day, to save energy. Try to keep temp in room between 75 - 80 degrees F and humidity between 50% - 60% during flower. I'm going to raise temps to 80 F - 85 F and humidity to 60% - 70% on next grow and see how that works. I believe air movement is also very important.

but veg must be a breeze for you. your plants probably get nice and big before flower. i need so many humidifiers to get it where that chart says it should be.

 

[Vegan4life]

but veg must be a breeze for you. your plants probably get nice and big before flower. i need so many humidifiers to get it where that chart says it should be.

Yeah my wife looked in my tent during veg and said "Holy shit"!!! She had never seen fan leaves that big before...

 

[Dusted]

I live with really low humidity. For the next six months I will have 40% RH even with five fairly large plants growing. My grows have never been influenced significantly by low RH during vegetative stage and flowering really likes low RH.

 

[Jackalope]

Humidity has never and will never be a problem for me. We never get high levels for any amount of time. My first few grows when I started back to indoor growing. Where in a huge bedroom with the plants pretty well spread out. Humidity was in the 30's to 40's at best. I thought the plants did fine till I saw what the did in a tent which traps some humidity. It gave me a much needed boost in production.

To start I never even check it. I just grew with what I had. Now that I know how much it effected the plants I keep a eye on it. My humidity is better but never always good. Because the low humidity from the natural air. Humidity fluctuates regularly throughout the day and night. With a tent I can spend a lot more time with humidity levels in the 40'sand 50's

Adding humidity is the only thing I could do. It would also add cost plus put me at risk of too high humidity is something went wrong. For me it is like temp. I found I can grow in lots of different readings. In areas that have High humidity that is a whole different story. If things go wrong for me I loose production. Humidity issues in high humidity areas go bad and you could loose a crop.

Like temp it is something that creates problems for only a few people in certain areas. Temp and humidity go together. When you can not control everything. You control what you can.

More and more today. You are finding strains that work in lots of different environments. Strains that do well against molds and mildew's are great for high humidity places. Lots of strains out there that do ok in lower temps. Once we get to the point that we can trust what the breeders are saying. It will be easier to find the right strain for the right area. We all have one of these issues to deal with at some point.

 

[Finnicki]

I am in Michigan. Last winter our home and basement were insulated. Dats guud. Never thought I’d ever be growing this plant. Anyhoo, temp in grow room is 66-67 now. I have an exhaust fan (Vivosun) and a charcoal in-line 6” filter. This runs to a hole
in the chimney wall in basement. When fan is off, cold air comes down from outside and flows back into room. Don’t know how cool it will get this winter down there. It IS warmer than past winters there. I can run a 4” pipe off a main rectangular duct. Heat would come into room high on the wall. What temp is too low for these plants? I could put an electric heater on floor next to plant as well. I have four, 2’x6’ silver panels around plant now. Who shortens their light times to duplicate nature during winter? I’ll stop now.

 

[Jackalope]

Temps in the high 60's is doable but it should be warmer. My temps last year ran between 62 and 74 most of the time. They grew but didn't produce much. Sounds like you are growing them in the room and not in a tent. A tent would help keep warmth around the plant. I would highly suggest running a tent in the room. Your dark time temps will still be low but when the light are on you should have temps in the 70's. The tent would help hold heat that is going straight up away from the plant. It is also helpful to put some kind of insulation between the cold floor and the planting pot.

If cold air comes back through into the room you will not want to turn the exhaust fan off. You don't need anymore cold air. When I grew in my basement. I had a similar set up and had thought about using the chimney. I ended up venting right into the room to keep the warmth. If you do this you will need to plug the hole where the cold air comes back in. Letting a small amount of outside air won't hurt.

I am not sure what temps are to low to grow in but you are might close to it now. Find ways to get more warmth the grow area. Yes people recreate winter light times. That is when you drop the lights back to 12/12 for flower.

 

[Finnicki]

Smell and the grow light color being seen have kept the location in the basement. Windows are blocked. We have an upstairs in this ole ancient haus with floor registers. 70 is what we keep it at for us and our parrot on the first floor. 50% RH. I want to keep the basement cause of newer wiring. LED 600 light draws little and so does the fan, I think. Decisions, decisions. We received our grow bags this am. Planned on setting the bag on an open wire chair frame. So bag will be off the cold floor.

 

[Finnicki]

It was 64 in the room this am. I close the door to that room to keep it dark. We have the lights on one switch down there and there have been times we have gone down there during the 12 off period. Are
grow tents safe to place a heater inside??

 

[Finnicki]

Are these grow tents guud enough to hold heat for hours if I used a heater for a few minutes inside the tent, then removed it?