70's natureboy
Well-Known Member
Over watered and not enough light. Potting soil makes house plants grow nice and slow and retains lots of water. Flushing it is drowning it.
Nutrient Lockout?
- Thread starter Umbra40
- Start date
Cool. So, your aim is to get the leaves standing up again and get the plant back on its feet. It's in a right mess and I'll explain what's causing it so you can avoid in the future.
First problem is your lights are far too close. The reason you see the sharp curling towards the ground of the foliage is because that's the plant's response to protect itself. It's trying it's best to shield itself from light it can't process. It's trying to shut down it's metabolism and, as best it can, block out the light.
Raise your lights immediately to at 36 inches above the canopy at the closest point. Keep the light at full power, but raise it to a minimum of 3 foot. Immediately your plants will now be in a position to start to recover.
For a plant to efficiently use light it needs to be healthy and have an environment in which it can grow quickly. That means bringing up temps to a level where the root system is warm and the air temp promotes transpiration. The general warmth also speeds the plant's metabolism and at that point, when you add in intense light like LED, you'll see the kind of growth you're looking for.
Get a heater with a thermostat and set it to above 72f. If your pots are raised up off the floor that'll take care of the root temps as well. Lower your extraction too, this will create a warm humid environment and that helps a lot.
Now you need to make sure your soil is right, so wet it with a base feed of 1.0ec and let it absorb. half an hour later water it again, this time til you get a good half a litre/quart of run through.
Now leave them in those conditions for 48hrs and take another picture then.
FrenchBaked
New Member
Issue from my experience is likely liked to municipal supply water, plants looked exactly the same and PH was to acidic. Try using rain water if any of your friends own a water tank unit.
I think municipal water varies greatly depending on region. Mine is pretty close to neutral, but that's something to consider. At work we have well water, so I could try that.
I agree with you on most points. I think the addition of some sort of low wattage heating element on a thermostat would be beneficial. I have a humidifier on a humidistat already, some computer fans moving around air slowly, and the exhaust fan only only kicks in when it hits 79 at the canopy and runs until it's back down to 76, which doesn't happen too often this time of year when no one is home. I water slowly and water until there's plenty of runoff. Prior to this week I had not been monitoring EC going in or coming out, but I will do that going forward.
The only thing I'm unsure about is the light. Right now it's 120W watts shared across 6 panels equally spaced in a 4x2 space. Specs aside, it's only 33,000 lux at the canopy, which is on the lower end for vegetation. From what I gather online it seems like with light burn the highest leaves get yellow and sometimes scorched and they act actually curl up or canoe a lot of the times. It seems more like a nitrogen deficiency because the lower leaves turn fully yellow and die off, like the plant is cannibalizing itself. Before you posted I gave it a heavy dose of fertilizer with the watering about 40 hours ago. I'm going to give it until I see how the new growth is doing. I can always adjust the lights if that doesn't seem to do anything.
Thank you for your through response.
You don't have light burn, you have light stress. They're very different things.
Light stress comes about when for whatever reason the plant can't process the available light. Continue to give it that much light while it's in a state of stress and you just weaken it further.
Light burn is exactly that, it's burn or bleaching from a source which is too bright or hot.
That's not what you have here and you're right, 120w from that far away won't burn them.
Whenever you see your plants looking like that, raise your lights to lower the stress to them.
Whatever the underlying cause of your issue, one thing your plants are showing you is there is something wrong.
In that state they won't be able to process the light and it'll cause more breakdown of cells and poor brittle growth. The longer they're in that state the less full the recovery will be. It's up to you if you want to learn by trial and error because they're your plants. But I've seen that issue first hand when I started growing with LEDs and I've since solved it and am passing on the knowledge which I guarantee will - Unless there's an issue with root rot or aphids or some other serious problem - turn your plants around.
You don't need to try well water either. It will make no difference to your grow if your tap water is even half decent and your feeding regime is ok.
You don't have a nitrogen deficiency either. Any skilled and knowledgeable grower will tell you that's not how a N def manifests.
With all due respect, the internet is filled with people with little experience or random suggestions which are based on a lack of expertise. It makes finding a solution to a problem a pain in the ass, because here you are potentially ignoring the thing which would immediately solve your issue, and possibly bringing buckets of well water home from work to feed your plants with... which might give your arms a workout but do nothing for your plants.
At the very least, leave the well water where it is.
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You're right, I misinterpreted what you were trying to convey. I agree with you, I don't think it's light burn, but in its current condition this seemingly normal amount of light may be doing it more harm than good. I dimmed it down 33% just before lights off last night and may go further pending evaluation.
I have these plants in a 4'x2'x3' high cabinet which was intended for veg. The idea was to keep it short and have many lights closer at low power because of the height restriction. Atop this cabinet I have a 5' tall tent intended for flowering which is currently devoid of plants. I don't want to put them into flower in their current state, but they might have to go in there simply because of their size at this point.
Here's a picture from this morning. At this point it would've only got reduced light for 3 hours, so it's hard to say how much that influenced it, but on the whole the combination of ideas in this thread is seemingly to help them recover.
