hi guys and happy to find you. its my first grow and i need some help regarding sunlight and heat . i have 3 autoflowering girls in pots growing outside . i dont know if the heat is too much for them . i live in greece . the pants are exposed to really strong direct sunlight reaching temps of 30-40 C with humidity around 25-30 . offcourse i water them often and till now i havent had a single issue . i am at week 4 . but as the summer and sun gets more intense i worry about them . should i be moving them into shade ? should i be changing spots for direct sunlight? should i be spraying them often? please provide me with info . also i need to tell you that after 8-9 o clock i am moving them inside a tent with strong cfls untill the morning sun where i move them back outside. in the tent i emulate same conditions regarding temp and i give them a bit more humidity around the 40s. is that a good practise or is making more harm? i will be gratefull for any help. thanks
Hello, and welcome, I would think from what info you have provided that you should be ok with your game plan you've got. As they get older and bigger, you will want to provide as much light as you can. Cannabis is an extremely light hungry plant so I dont believe you will have a problem with too much light.
How old is the plant? 30-40C (86-104F) is too high of temperature for growing cannabis. I'm surprised the plants haven't shown signs of heat stress yet. 21-28C (70-83F) is a more comfortable range.
thats what i read around too. and yes in greece this time of the year the sun is too strong . should i be moving them to shade? should i be sparaying them often ? what can i do?
@Michalis Krokidis Yeah I can see signs of heat stress - curling leaves. Giving them some shade each day should help. It's impossible for us to tell you exactly how much. You'll have to experiment on your own. Once those leaves aren't curling anymore then you know the plant isn't experiencing heat stress anymore.
Chris - since i had a couple of failures recently and had to rethink and plan things out i did however have a small testing set aside
now i do agree that some plants really love the lower temps from about lowest at 68 to 70 and the high point being in about or around 76 to 80 - about a common average for most
the ones i have now at about 45 or 46 days old they look great but this was a kicker for me and caught it fast
for about the first 10 days after they got established from sprout ( about 2 weeks ) i did notice very dark green leaves and started to curl up - now during this the temp was about 71 to 73 with a humidity of about 43 %
i gave it a bit more heat thinking it was a bit low so it was then at about 75 to 77 and still with about same on humidity - this seemed t make it worse and looked like they were going to wither away if kept going as it was
so now heat not answer - now to cool it down - i got the temp down to about a steady 68 - things started to look better but still off - so i lowered again and now running at or about 58 to 62 and they are striving like the Fourth of July in May lol lol
humidity did fluctuate a bit before getting stable at about 46 to 48 % at all times - now this might be a good thing also to look out for with some strains - i have found that some like very cool temps to strive while others like the high heat
i did post a recent picture in the other forum post about Fox Farm Nutrients and will post here also
is it possible that i might have like a Afghani Kusch or along that line of lower temp plants ? - i do remember reading something about some liking the cooler temps from like 50 to 60 degrees
if look at the bottom just to the left there is one tiny plant that did not recover like i thought it has stayed about the same looking like over fed and over heat leaf curl
but the rest of them really look fantastic and this is only been one actual feeding per the FF schedule after a did a major Sledgehammer flush -
5 gal paint bucket with holes in bottom only
soil is 5 Lb of Nutrient free potting soil 1.5 Lb of Pete Moss 3 Lb of perlite 4 cups beach sand 6 to 8 cups broken up popcorn packing material and any or all stalks from old harvests
now this does hold very well in moisture from about 20 to 30 days or higher before next feeding -- original flush start was 3 gal of Sledgehammer and 1 gal of plain water planted on April 9th and did not do the first actual feed till May 17th
this one i keep at about steady about 58 degrees with a 38 to 40 humidity
now i am thinking i might have to jump the feedings or try to stay close to the schedule as possible at a more advanced nutrient plan combination - half veg and half flower even just might wing it from the hip lol lol
thanks to all and have great grows - Peace to all with Growers Luv
thank you so much for answering . the plant now is at the first week of flowering. i have been having it since day one in 24 hours light. do you think i should move it to 18/6? will i stress it by changing the chedule? is it wise to do that or just leave it as is just with more shade during the day? thank you for your time
Changing it from 24/0 to 18/6 won't have a negative impact on it. There has been at least 1 study which shows 18/6 is better for the microbial population vs 24/0
Sorry I didnt realize your temps were so high, Im a stupid american and celcius is chinese to me lol. Your temps will definitely play a part and the strain can matter as well. Indicas come from cooler climates and therefore prefer cooler temps and sativas prefer warmer temps.