heat problem during day. Light cycle change may solve?

First time grower (indoor)
hi i passed 1 month and 3 days since seeds were planted. All first set of bottom leaves turned yellow and fell off (and the cotydelon leaves too). I think photosynthesis has stopped because the heat has reached to 40 degrees C (104 F) almost everyday, which pretty much must have slowed down the growth and will most probably decrease my yield. The summer has never been so hot here, I'm thinking of changing the light cycle from day to night - At the moment I have 18/6, from 9pm to 3 am darkness.Maybe if I keep the lamps on for 12 more hours and then turn them off, would that work? Or would I freak them too so much? In other words.. I thought of having darkness during day between 9 am to 3 pm (instead of 9pm-3am), because thats when the heat is at most outside during the day.

Things I've tried: I have tried to open the windows from both sides the whole day (I got them on the top floor of the house) but it wouldnt really help plus I'm afraid of getting the garden infested even if I use insect nets on the windows. Already have thrips and aphids which I havent started to work out yet. The room is about 6,5 m x 3,5 m (21 feet x 11 feet~). I shortened only one side of the room with wood and plastic (similar to what jorge cervantes shows on youtube, to get u a perspective) but it doesn't seem to help the heat so much. I was happy in the morning because the heat was actually perfect (27 degrees C) but now after a couple of hours it has reached to 36 degrees C and going up...


lamps: 3 - 400 W MH and 2 600W HPS
air circulation: I have a 8 inch inline fan (1000 cubic) blowing air out and a 6 inch fan (150w) + 3 fans blowing on plants

Their length is +- 8 inches,
They got 4-6 sets of leaves

Thank you for any advice given, I'm trying my best to reach optimal temperature (somewhere 24-27 C would be fine). I have white widow, super critical, ams and some autoflowerings.

(p.s. the house is 150 m2 and one of the rooms downstairs have 2 lamps 600 W, which might be the reason the heat rises in the house and reaches the ones on the top floor... that's why I made the oneside wall to try to keep the top floor sealed)

This post might be in the category "plant problems" but I think I'm not the only one having this thought so maybe it it's ok to post here.. my apologizes

First, make sure you don't burn your house down because it sounds way too hot. Second, pictures help, but it sounds like you already know the main problem, HEAT. The plants will not thrive in temperatures above the optimal range (for me it was always 70-80 Fahrenheit).

If the temperature is too hot, the plants can not effectively take in carbon dioxide and release water vapor through their leaves. Try investing in an air conditioner, removing lights, running only certain lights at certain times, whatever you can do to get the temperature to the optimal range.

Remove the bugs. Get a good spray and get rid of the intruders as fast as possible. The bugs will never help, could lay eggs, and will just lead to more bugs. I recommend an organic hot pepper spray (worked for gnats and does not hurt plants).

Once you've solved problems one and two, see if the plants health improves and then start considering flowering. At this point you may have already diminished the yield, but you can still finish strong and they should bounce back in the right growing conditions. Yellowing could also be due to overwatering, so be aware of this possibility when you are fixing problems. Also, you change in light cycle should not be a problem.

Best of luck.

U have tyo have cool air coming inside the grow area. top floor is always the hottest in the summer unless seariously insulated.

baddfrog0221 said:

First, make sure you don't burn your house down because it sounds way too hot. Second, pictures help, but it sounds like you already know the main problem, HEAT. The plants will not thrive in temperatures above the optimal range (for me it was always 70-80 Fahrenheit).

If the temperature is too hot, the plants can not effectively take in carbon dioxide and release water vapor through their leaves. Try investing in an air conditioner, removing lights, running only certain lights at certain times, whatever you can do to get the temperature to the optimal range.

Remove the bugs. Get a good spray and get rid of the intruders as fast as possible. The bugs will never help, could lay eggs, and will just lead to more bugs. I recommend an organic hot pepper spray (worked for gnats and does not hurt plants).

Once you've solved problems one and two, see if the plants health improves and then start considering flowering. At this point you may have already diminished the yield, but you can still finish strong and they should bounce back in the right growing conditions. Yellowing could also be due to overwatering, so be aware of this possibility when you are fixing problems. Also, you change in light cycle should not be a problem.

Best of luck.

Click to expand...

haha I know it's crazy I can laugh about it but it makes me sad :/ I will change the light cycle on the topfloor today, that would hopefully decrease the temperature. I'm sorry I got no cam or Iphone/android to take a few pics.. really want to though, to give you a better detailed description.

Tomorrow I will get a spray to remove the bugs. I know I got aphids but the "thrips" are oval and yellow. I can see them without magnifying glass but of course I notice their oval shape using 3x-6x magnifyer. Really want to take a picture to be sure what it is. Done the research but my opinion is still newbie. Got white spots EVERYwhere on some plants. ;/ hope it's not spidermites.

Thanks for your help mate! Just of curiousity, I have 3 babes in 3 gal pots (half filled with earth..) and the plant is about 4,5 feet 19 days into flowering (3rd week). What would be worse - Transplanting the plant to the same pot but with more soil or ride it out and see the sad flower asking for more space.. which will decrease the yield...

peace

I am sorry for your terrible growing conditions...
Heat above 100f for any length of time your plants are done...
two or three different types of bugs? If the bugs don't kill what remains of your plants, the killing of the bugs, will kill your plants...
You might need to start over....
However, Neem and H202 will kill most of the bugs without killing your plants...
If you see large group of critters on a specific leaf, chop leaf, and let it leave your house.
Insect soap also works to a degree...
I feel for your little girls, they are being tortured...
Good Luck, you will need it....

Thanks for your help mate! Just of curiousity, I have 3 babes in 3 gal pots (half filled with earth..) and the plant is about 4,5 feet 19 days into flowering (3rd week). What would be worse - Transplanting the plant to the same pot but with more soil or ride it out and see the sad flower asking for more space.. which will decrease the yield...

Click to expand...

You can do this, it might help...
Before your next water, [plant is easier to do when slightly dry...
Grab trunk of plant, gently pull out of pot, if it slides up, then pull it all the way out, and dump extra good soil under plant and then gently put it back...
Have soil ready to put in old pot...
Then water it like normal...
Again...
Good Luck!

thanks for all your help.

shit I feel so sad right now, I don't know what to do. :/ I guess it's like this for most people the first time. arghhh f****** heat!!!!!!!!

thanks anyway

Run your lights only at night that will do the trick 8 pm to 8 am

Ac & cooltubes....im on 3rd floor growing so i know all the fans in the world aint gonna help u when those summer temps begin to climb.

Freeze a few large bottles of water. Use two liters or gallon size bottles. Rotate them into your grow room so that while some freeze, some keep it cool. Put a couple frozen bottles by an intake fan when your lights turn on. This may seem like a lot of effort but it will keep the temps down.

thanks for all the tips. gonna get an ac 700w hopefully it will fight harder than the heat from the 5 lamps.. Bottle water thingy will be tried first!!. I hvve some pics now, wohoo here they are:


not great photos this computer cam is horrible... but this autoflowering plant started a few days ago... look how small it is. I got llke 4-5 more weeks on that one before its finished. It's ful of thrips and aphids. How much gram do you think I'd get to smoke?

Other question: my WW, and super ciritcal strains have the same size like the pic but a bit shorter. Im going to fight aphids and thrips on the feminized normal seeds, and reconsidering to put them into 12/12 after spraying them at least two times. (heard its better and easier to do that work during veg). but what would the yield turn out to be on a normal feminized white widow plants in my circumstances ? (super heat and a lot of 'tropical raining ' weather... lol) dont forget how small it is.. with 6 sets going to 7th (atm). Thank you for the professional answers. I apoligize for the bad typing, took a stilnoct but couldnt get to bed before doing this post =P my apologies

Definitely kills the bugs, fix the heat, and figure out a good watering system, then worry about yield.

The pictures look like new clones, are those the only plants affected? How tall and wide are the plants you plan to flower? Yield will depend upon a lot of different factors such as: height, width, age, and environment. Also, yield is not an indication of quality, i.e. with the stress your plants have been through, they may produce a good yield with poor quality.

From my experience, a plant that is about 4 feet tall/untrained will produce between 1-2 ounces of smokeable product. It can be more or less depending upon the age, environment, and species. I think the most I ever got was 1.5 ounces from one plant, but that's just an approximation, I don't have the detail in front of me. And, it was from bagseed that I learned to grow with.

Best of luck to you, hope everything turns out well.