Heat stress in Flowering, any tips?

Hey everyone, it´s me again :smiley: I have some more questions for my 3 plants.

I flipped them 7 days ago but had some heat issues I just now realized. How you might ask? Because my slow brain thought the best place to measure temps and RH is at the bottom of the tent instead of the canopy :man_facepalming:t3:

i even blew air from the dehumidifier directly in the intake vent because the RH at the bottom rose up to 70. Temps stayed between 25-27C (77-81F)

Today I attached the hygrometer to a string at canopy height and turns out the RH isnt the problem but the temperature is. Over the day it crept up from 25C (77) to a max of 32.9 C (91F) and RH of 40%. I even put it above the light because i read the direct light can alter the real temp but the readings stayed the same. The leaf temps were 28.8 at the highest canopy point.

I´m using the LUMATEK ATS200W PRO on 100% power since the flip, so i think the heat was that high all 7 days. I fed 50% bloom nutes one day before flip after defoliation. They are still growing but not as much as i expected during their final stretch (which might be a good thing since my tent would be too small). Also all the lower leaves turned yellow and died off but i figure thats normal since no light at all was reaching them through the thick canopy

So here are my questions:

  1. They are all showing pistils/Stigmas but do they look behind or even damaged because of the heat? its my first grow I have no idea how they are supposed to look like after 7 days of flowering.

  2. The top one is showing N toxicity and the bottom left CAL deficiency. I think its caused by the heat, forcing the plant to transpire a lot faster and uptake/deplete nutes (prefertilized soil should be depleted by now). After schedule i´m supposed to feed today. Should i still do that or just water?

  3. Any tips on decreasing temps? Ordered an oscillating clip fan but wont arrive till Thursday.

  4. cranked down the light to 75% but would like to keep it at 100% if possible. Can I keep it at 100% and lower it to 75% if it gets too hot or is fluctuating light intensity bad?









Hope that wasn´t too much at once :slight_smile:
As always any piece of advise is appreciated!

Cheers
Zero

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What’s you lighting intensity Growmie as in PPFD or DLI? PH looks like it’s off and a calcium deficiency but coukd be PH related. What’s your feeding routine, PPms and PH going in and the run off of these 2 :love_you_gesture:

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Dont have a ppm reader or ppfd meter ppm reader hopefully arrives thursday with the fan

according to the manufactuer at 100% its 650-800 ppfd across the canopy (they tested with 0%reflection though) lightcycle is 12/12

I only fed them veg nutes once after that they showed N toxicity and the mentioned bloom nutes at 50% last week. Still some dark green leaves and minor clawing even though the soil should be depleted of nitrogen by now

Was supposed to feed today but just gave water. pH in is ~6.3-6.5, usually 1.6 litres. i only watered till runoff once 2 weeks ago, pH was 6.7, 6.5, 6.6. The manufacturer for soil and nutes says its not necessary to water till runoff.

How about the colas/bud sites? Do they look like they supposed to?

Cheers

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What soil and nutrients are you using Growmie? Any synthetic fertilizer should be fed to liberal run off to rinse away the extra salts. Not doing so can greatly affect the PH :love_you_gesture:

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BioBizz light mix as soil and
BioBizz fertilizer starter kit containing bio bloom, grow, heaven, top max and root juice (not using that anymore since its for veg only)

Not sure if i’m allowed to post a link since it could be considered a ‘rival’ company :sweat_smile:

i guess its a synthetic fertilizer, so i should water till run off everytime? Last time i definitely had to overwater them somewhat to get the runoff (slightly above 3 litres)

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For soil grows it’s best to follow a drench to drought routine using synthetic fertilizer with the drench to 20-30% run off. The run off acts like a soft flush expelling the accumulated salts resulting in a happy root zone. Organic soils would require no run off but needs to remain damp to keep it alive :love_you_gesture:

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Ah okay got it. One last question: should i also water till runoff when i feed? Am i not wasting nutrient solution if it comes out the bottom? :sweat_smile:

Hey @Storm @kellydans @2GreenThumbs @Mothman @Riskguy ,
since you helped me on my last posts care to chime in? :slight_smile:
This post doesnt seem to get answers beside OG’s

Would be appreciated! :call_me_hand:

Cheers
Zero

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Og is a solid grower. Temps getting to 90 plus a bit happens. My hlg gear was hard to keep cool summertime here. Hit plus 90 a lot. Not an optimal temp but a WORKABLE 1. My solution was increased airflow and watering. Switching lights from day to night. Small tweaks as can do them add up. Airflow was my priority especially exhaust. Lungroom is very important and i freeze mine out. A foliar calmag regimen for a bit looks like it might help the calcium dots. Some nutrient lines actually need it. The girls look pretty good. Still filling out. Look up your nutes. If living you can go to a moist soil. If not then a drench/drought as OG suggested. Runoff can be minimal. Just stage water. Give time for soil to absorb the water during the process. 1/4,1/4,1/4 etc. If testing a good runoff would be desired. Otherwise a little to none is fine as long as you wet it well and even. A 3/4 drench is fine also. Just have to do it more often. Just my thoughts.

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Just an aside here. Sometimes when 1 of our respected growers is leading correct the rest of us just like and dont rock the boat. If we catch a miss or see something then we pop in and comment. Your looking just fine right now. Keep ph in line and follow nute suggestions. Dont add extra. Wont help…only hurts most times.

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Ok thanks! I just heard that such high temps can evaporate terpenes later on. I was worried since its probably gonna get even hotter in august and i’m already struggling

Can’t control the lungroom that much since its in our big staircase but i added a fan to get the exhaust air moving more. Also made some adjustments to the tent. Straighten exhaust hose, opening more intake vents
Already down to 84F max yesterday and the rest of the week is supposed to be cooler anyway

Didnt mean to sound ungrateful to @OGIncognito advice, i’m definitely gonna try his suggestions! Just thought the post might be overlooked somehow, thanks for the clarification.

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Solid pointers from @Storm Grow Bro, often times well tag team questions with our experience on what works and what doesn’t. Often times experienced growers will read post and not have anything to contribute if they notice others are guiding the new grower in the right direction. Best way to get traffic to your journal is get out and visit other journals and comment. Keep this post going as your journal Grow and get out and mix and mingle with the neighbors :grin::grin::love_you_gesture:

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Looks like you are covered. Some will turn down their light the last week before harvest if the temps are high…Irun my tent around 84F…but get spikes higher. Plants are looking fine.

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Think i’m gonna do that. Can i change the category/topic to grow journal? Didnt see where i could edit that

Ppm reader arrived today. Honestly i have no idea what to aim for, only know that it measures the parts dissolved in the water :joy: never read into that topic thinking its too advanced for the first grow

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Definitely going to feed tomorrow because a lot of the lower leaves are yellowing/dying. Not too worried though since i was VERY conservative during first defoliation and the leaves were deep under the canopy and didnt receive any light

Clip fan also arrived, right on time since i discovered some wet spots on touching fan leaves

Biggest concern right now is the stretch. They grew a lot last 2 days and are closing in on the light. Can raise it 10" once more to the support bars using zip ties but after that i need to tie the main branches to the side or into the net

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I do like to water to run off Let pot stop dripping before returning to tent.

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Stay with us. Some of us disappear for a few weeks but always return. The frequent helpy helpers always are around. You get 5 or 6 different solutions to choose from typically. You will NEVER be harrassed here. The asshat types make it 2 or 3 posts and we collectively have them removed. Many of us have been up here years. Our journey in growing has improved even for the ones who came here established. Glad to have you. Pay the knowledge you gain forward to the new growers.

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Yeah i’ve seen a lot of you guys on so many posts i read haha

definitely my experience. I’ve browsed some other forums where the poster gets belittled or even insulted for not knowing/doing something. And people always argue about the ‘right’ solution in the comments instead of helping the new grower. Here everybody is friendly and truly wants to help!

You guys really understand that there is no golden route to growing and it often is subjective liking.

Will give an update about the ladies tonight after feeding

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Was a bit of a hustle but I closed the tent right when the lights went off :muscle:t3:

Plant 1 Plant 2 Plant 3
Water total 2.4 litres 2.4 litres 3.1 litres
Nutes 100% Flower Week 2 100% Flower Week 2 100% Flower Week 2
PPM (in/out) 650/630 650/504 762/560
pH (in/out) 6.4/7.0 6.4/7.2 6.4/6.9

Note to self: think of names for the ladies :smiley:

Got around 10% runoff, couldnt get more due to the time. Now i gotta do some research if the PPM is good or bad :joy: pH seems a little high as well gonna research that too.

Found out that the fertilizer is organic and I´m supposed to feed 2-3 times a week instead of 1 like i was doing :man_facepalming:t3: will give them 100% from now on since i was holding back way too much.

Definitely waited too long to water again (almost 3 days). Soil was very dry and the lower leaves were drooping with their stems. After feeding/watering almost instantly perked up a bit

Did some defoliation of dead/crispy leaves (under canopy) that were easy pulls. Left the rest hanging since it could´ve been underwatering and they might recover.

Before:

After:


got some branches that won´t make it to the top (will cut them day 21 of flowering) but a lot of bud sites breached through the canopy and all of them are showing signs of flowering :heart_eyes: pistils got a lot more as well!


still the only worry at the moment is the height, haven´t gotten to read into LST or super cropping, gotta do that since I´m away for the weekend.

That´s it for now!
Cheers
Zero

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Got not a lot happening the last 2 days. Tent got a little hot (max 89.6F) again today. Couldnt open windows because it´s was raining mad last night, humidity easily was at 80% outside. They all look happy and healthy.

Biggest change are more and more pistils, especially on the side branches.

Main Colas:


Side Branches:


Detected some more browning leaves on the lower parts. Could be due to me feeding only once per week instead of the recommended 2-3 times or the lack of light since they are deep inside the lower part of the canopy.

Going to pluck them right before feeding tomorrow morning.

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