11 week old plant suddenly drooping like crazy

Hey guys! First post here so sorry if this is the wrong subforum or something.

First a bit about my grow:
I’ve been growing a jack herer for around 11 weeks, outside for the first 9 weeks or so and then I took her inside as I live quite far north.

My grow area is about 15 sq. m and is unfortunately sealed as I’m not able to provide air exchange to the room. My lamps are a 600 watt MH that I used for the first week inside to help her recover from a supercrop that I had to do because the plant was to tall for my grow room, and a 600 watt HPS that I started using around 4 days ago as I switched to flowering light schedule.

The nutrients I use are Advanced Nutrients sensi grow and sensi bloom.

The first week inside went well. I had pretty much no issues. The plant recovered quickly from the supercrop and a couple of days ago I decided it was time to set it to flower. I switched out the MH for the HPS and set the light schedule to 12/12.

After about 24 hours all was well and I proceeded to give it about a litre of water as I had done all days before. I come back 24 hours later (yesterday) and the plant had started drooping quite a bit in the upper leaves. I did some quick research and figured it was most likely due to overwatering, which made some sense considering the lights now were on 4 hours less meaning the water dries out a bit slower. Relieved that the issue wasn’t anything serious I simply refrained from watering the plant for now.

Fast forward another 24 hours and the situation has gotten considerably worse. The whole plant is now drooping like crazy and I’m now trusting in you my fellow growers to help rescue my poor plant.

Thanks in advance!!

TL;DR : My 11 week old plant has suddenly started drooping a lot overnight some time after I switched to flowering. Skipped watering yet problem has gotten much worse 24 hours later.

Pictures below. The ones taken with flash are taken 24 hours ago and the ones with light on are from today.

Might be root bound , what are your temps?

how close to the light is it?if you put your hand on top of your plant does it the light get warm or hot right away

Temps are not too good I think. I actually don’t have any thermometer although I’m planning on buying one very soon. My guess is that the temperature while the lights are on probably get as high as 30-35 and maybe 20-25 during lights off. I checked the roots and while the roots are visible on the sides and bottom they’re quite sparse and it doesn’t look rootbound at all compared to the pics I’ve seen of rootbound plants.

The lamp is around 40-50 cm away from the plant.

Thing is, if temperature was the problem how come it was fine for 8 days or so despite the high temps and now suddenly starts drooping?

Hummy341 said:

Thing is, if temperature was the problem how come it was fine for 8 days or so despite the high temps and now suddenly starts drooping?

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You switched bulbs

Herb & Suds said:

You switched bulbs

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True, but HPS’s don’t produce much more heat than MH do they? And it’s only on for 12 hours at a time rather than 18.

Hummy341 said:

True, but HPS’s don’t produce much more heat than MH do they? And it’s only on for 12 hours at a time rather than 18.

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Heat is the issue not light period buy a cheap hygrometer/thermometer for about $12 at a box store

Poor watering habits as described in opening post.

hotrodharley said:

Poor watering habits as described in opening post.

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Could be.. So I should water it less right? Why did this come so suddenly though? My watering hasn’t caused any issues until now.

Herb & Suds said:

Might be root bound , what are your temps?

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Root binding dosnt cause droop.

hotrodharley said:

Poor watering habits as described in opening post.

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Exactly my thought. Water untill throughly saterated. Dont water again untill pot is dry.. Your only giving them a ltr a day over watering probably isnt the problem. The top couple inches get wet but the inside and bottom of the pot gets dessicated and roots dry up and die.
Not mutch info in the post other things that cause droop are n tox and salt build up.

Dynamo626 said:

Root binding dosnt cause droop.

Exactly my thought. Water untill throughly saterated. Dont water again untill pot is dry.. Your only giving them a ltr a day over watering probably isnt the problem. The top couple inches get wet but the inside and bottom of the pot gets dessicated and roots dry up and die.
Not mutch info in the post other things that cause droop are n tox and salt build up.

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I believe being root bound restricts water uptake and under watering will cause droop in my opinion

Dynamo626 said:

Root binding dosnt cause droop.

Exactly my thought. Water untill throughly saterated. Dont water again untill pot is dry.. Your only giving them a ltr a day over watering probably isnt the problem. The top couple inches get wet but the inside and bottom of the pot gets dessicated and roots dry up and die.
Not mutch info in the post other things that cause droop are n tox and salt build up.

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Thanks for your advice!
Thing is I always check to see that the top inch is dry before watering and make sure there is some runoff.

Hummy341 said:

Thanks for your advice!
Thing is I always check to see that the top inch is dry before watering and make sure there is some runoff.

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Water by weight. It's really the safest way to prevent overwatering. Also uuse a narrow skewer or chopstick to pierce all the way to the very bottom of your containers. You cannot hurt healthy roots and it aerates the medium. Then water slowly and allow it to sink in well before continuing water.

Being root bound you have to water more often but they will not droop because they are root bound. They droop because they suck up the water faster therefore they dry out faster and when they dry out they droop. Check out a beer cup chalange.

Hummy341 said:

Thanks for your advice!
Thing is I always check to see that the top inch is dry before watering and make sure there is some runoff.

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If you have excessive root temps you may be losing DO2. I doubt this is a sudden thing for the plant even tho it might be for you. More likely it is an accumulation, now the plant is showing visible strain under the environmental conditions. You really ought not to let your plant dry up. Ideally cannabis likes soil moisture between 40-60% and root temps at an average under 25C across a night to night cycle.
How plants balance energy in a dynamic environment is worth understanding. Better to keep soil moisture between the levels above, and the root temps at about 21C as an average. At 21C water holds 7ppms of DO2, levels under 6ppms are bordering anaerobic. The hotter the root temps, the less availability for Oxygen. If you cant control the heat, humidity, CO2, and moisture, you are always going to struggle to attain reliable harvests.
Also, please note, standard room temp gauges do not take in to account UV radiation, UV does not show up on air temp gauges because it passes through air without transfer, so if you are serious, invest in a laser thermometer so you can accurately take leaf, stem temps. UV energy is transferred on contact with solid objects, eg your leaves, plant pots and so on. You will have felt the impacts of UV on your arms for example in summer or during high light days.
Plant canopy temps above 25C are not ideal for growing cannabis, certainly 35C is extreme and a substantial risk without serious design, additional CO2 and so on. try to maintain an average temp range of 25C or lower, so this means monitor you day and night temps. where day temps are above 25C you will need to counter this by lowering the night temps to maintain the average.

Plants have a tolerant range for stress and each one has a set day period of extreme risk. Consecutive days of say high root temps, or excessive canopy temps at these periods will certainly result in failure, reduced harvest and worse. Many plants can not be recovered after they have reached the limit at this key period, eg it is not possible to stop bolting once it starts.
Knowing your phenotypes is one of the only way to record the high risk periods and so dial any plant to your conditions.

you cant buy a nutrient bottle to fix energy balance issues, AC yes, CO2 yes, lower light umol yes, heating yes learn to water by knowing the rate of evapo-transpiration, not guessing, and try to get your environment to not peak beyond tolerant ranges, both low and high ends.

Hope that helps

Hummy341 said:

Hey guys! First post here so sorry if this is the wrong subforum or something.

First a bit about my grow:
I’ve been growing a jack herer for around 11 weeks, outside for the first 9 weeks or so and then I took her inside as I live quite far north.

My grow area is about 15 sq. m and is unfortunately sealed as I’m not able to provide air exchange to the room. My lamps are a 600 watt MH that I used for the first week inside to help her recover from a supercrop that I had to do because the plant was to tall for my grow room, and a 600 watt HPS that I started using around 4 days ago as I switched to flowering light schedule.

The nutrients I use are Advanced Nutrients sensi grow and sensi bloom.

The first week inside went well. I had pretty much no issues. The plant recovered quickly from the supercrop and a couple of days ago I decided it was time to set it to flower. I switched out the MH for the HPS and set the light schedule to 12/12.

After about 24 hours all was well and I proceeded to give it about a litre of water as I had done all days before. I come back 24 hours later (yesterday) and the plant had started drooping quite a bit in the upper leaves. I did some quick research and figured it was most likely due to overwatering, which made some sense considering the lights now were on 4 hours less meaning the water dries out a bit slower. Relieved that the issue wasn’t anything serious I simply refrained from watering the plant for now.

Fast forward another 24 hours and the situation has gotten considerably worse. The whole plant is now drooping like crazy and I’m now trusting in you my fellow growers to help rescue my poor plant.

Thanks in advance!!

TL;DR : My 11 week old plant has suddenly started drooping a lot overnight some time after I switched to flowering. Skipped watering yet problem has gotten much worse 24 hours later.

Pictures below. The ones taken with flash are taken 24 hours ago and the ones with light on are from today.

Click to expand...

This happens when i under water my plants, lift ur pots are they heavy?
dont forget when you put them in flower they stretch a lot in turn drink alot the mofo

SmileyBizz said:

This happens when i under water my plants, lift ur pots are they heavy?
dont forget when you put them in flower they stretch a lot in turn drink alot the mofo

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Hey and thanks for the reply.
Yeah turns out it was caused by underwatering, but I hadn't really read anywhere that plants got this droopy from underwatering from what I've read that's more a sign of overwatering which was what confused me. It's all good now though.

Hummy341 said:

Hey and thanks for the reply.
Yeah turns out it was caused by underwatering, but I hadn't really read anywhere that plants got this droopy from underwatering from what I've read that's more a sign of overwatering which was what confused me. It's all good now though.

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yo should learn about plant deficiency, all types, this will save you loads of time stressing about something that is nothing serious.