What is going on with my drooping leaves?

What makes plants rigid and upright? Turgor pressure. What drives turgor (daytime)? Mostly Transpiration. What's transpiration? Movement of water from roots up the plant and out the leaf. What creates the pressure from the drive? Osmosis. What's osmosis? Movement of water through one membrane to another. Normally in direction of higher salinity. Pottasium K is the nutrient responsible for inflating and deflating guard cells responsible for stomatal conductance. Stomatal Conductance is a precursor for photosynthesis to occur. Environmental conditions are fooked, I'd say the plant is protecting itself from losing all its water, high temps require alot more water to incorporate the process of transpiration. A cannabis plant will transpire 3x at 86f as it would at 68f. Around 90% of a plants daytime water use is for endothermic cooling of surrounding leaf called transpiration. If you 3x the rate you need 3x the water. Your plant is shutting down to prevent rapiddd water loss. Very hot, very dry. If plant was to continue full steam ahead she would burn up more water than she can replenish, as a response she is shutting down the waterworks to conserve what she has left before perma dmg is done. If the plant was actually spitting out the water it should, the temps would be a lower. You would be surprised how much cooling transpiration itself creates. Lots of water every morning, best of luck. The environment in the air dictates rate at which plant will eject water. The environment of the medium dictates rate at which plant will uptake water. Think of the plant like a bathtub with the faucet left on, you must keep the rate going in, in balance with what's going out. You do this through a balancing act of various cardinal environmental metrics. 01100001 01101110 01110101 01110011 advice is good for watering, I'm sure there is a 400 word opinion piece below this with everything you should do with regard to watering.

I just had a look at your profile and was hoping to find a grow diary there – that would have allowed me to give you a more precise answer. If you’re confident that all your environmental parameters are dialed in, I’d suggest taking another close look at your watering habits. From the two pictures you shared, your plants seem slightly overwatered to me. But it’s hard to say for sure based on just those two images. As for your actual question: Yes, cannabis plants are aware of the day-night cycle. Just before the lights go off (night mode), it’s completely normal for the leaves to droop a little. And in the morning, when the lights come back on, the plant needs some time to raise its leaves again. This is a totally natural process and nothing to worry about. Keep growing growmie!

Bottom of pot should never be dry.............poor watering habits. As 1001 said, fully saturate the entire pot until run-off and then do not water again until the top inch has dried out again. Heat is not an issue, I grow in 40+ temps outdoors and don't get droopy leaves...........its all about correct watering habits. At 29 degrees your plants will drink more, so you will have to water more!

just want to re-iterate.. bottom of the pot should not be the first part to dry unless you mean a very limited portion near drain holes.. so fix those watering habits before doing anything else. moisture should be highest deeper into pot that way roots grow deeper rather than superficially. They physically grow toward greater moisture, mindlessly.

bottom of pot was dry? This indicates some poor watering habits... i'm going to copy/paste from a different question asked at same time,lol.... /quote 1) fully saturate 2) wait for top inch to dry and repeat. is the simples way to put it... 'enough' drayback is the key and you don't want any wilt, of course. The volume required will be similar if you irrigate at same loss of weight from the pot. You don't choose the volume nor the time between irrigations. Context dictates these things not some top-down feelings on the matter. If not doing that, start. It may be the cause. Partial watering may be leaving certain zones of medium dry which can be difficult for roots that grew there and invites buildup of nutrients as moisture ebbs/flows around a dry pocket .. evaporation deposits more nutrients each time it happens, then goes back into solution when it gets moisture again etc... also, it trains superficial roots which are not ideal. if watering entire volume ever causes a problem, it is 100% the fault of how the medium was constituted. Simply watering should never cause a problem (assumes you don't water too frequently). Take your brain out of it. Simply react to what you observe. Give the volume necessary to accomplish the task and not some preordained volume you chose to give every 2 days. If that is 'soilless' you need 10% runoff to maintain nutrient levels. In soil, just make sure it is fully saturated with minimal runoff when things are healthy - i.e. don't waste your soil's amendments. I'd suggest more perlite mixed in... 50% of volume for high water capacity soils and 30% of volume for coco coir context. Both end up with same drainage/aeration properties. /quote So, 29c should be fine as long as your RH% is not too low. Early flower 1-1.2 VPD is probably a good target and you can go as high as 1.5 without too many issues later. (kilo-pascals). If using atmosphere temps, deduce 3-4F and reference a VPD table. Droopy as the lights turn on or at the end of the light cycle is not necessarily a bad thing if it is for a short period of time. Plants droop when the lights go out always. Node spacing does not indicate any light damage potential as it is tight (in a good way) and spaced out well enough. Could be your climate and amount of light provided being an issue. If VPD is super high, it can't handle as much DLI compared to a more moderate VPD. Sometimes these sorts of symtpoms take a week or 2 to present themselves from the point it became a problem. So, don't limit your thoughts to 'last night' etc. You want to be around 65% and that's still a high VPD. You go higher and you invite microbial growth -- which with extreme heat may or may not be a better alternative? It would be best to find a way to drop your typical temperatures below 29C. consider light cycle during night time... some electricity providers give discounts for off-peak usage too, so it might save some money, too. This won't do any miracles, but all you need is a couple C less, which is a reasonable expectation for night time light cycle.

Hey 👋 If everything seems to be fine with your watering, the rootcause is the high temperature. I had the same issue with my 2nd quick one run… outdoor, on the balcony (southside)… your plant will grow slower, but she will grow… So no worries 👊🖖🍀