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My lower leaves always curl down...reflected light off the Mylar, or something else?

Discussion in 'Indoor Marijuana Growing' started by vapeos, May 30, 2012.

  1. #1 vapeos, May 30, 2012
    Last edited by a moderator: May 30, 2012
    So, I have three plants that I just flipped to 12/12 a week ago. All of them have their lower large leaves curling down around/into their planters (Smart Pots for this run.) I've pruned several of those leaves, but the lower ones keep curling down, around the planters... And this has been the case for every grow I've done so far. I've pruned the leaves from the first 3 - 4 nodes on all of these plants.

    I'm using two LED panels right now, 500W total of LEDs (315W actual draw!), equivalent to about 1000W of HPS. However, I can keep my lights much closer than you could keep a 1000W HPS setup...and there IS a lot of light reflecting off the Mylar base of my grow tent (the entire tent is lined with the stuff.)

    So I'm wondering if those lower leaves are growing down because they're being shaded by stuff above, and the reflection off the Mylar might be brighter than the direct light...

    Anyone else run into this? I'd put down something dark under the plants, but I tend to splash nutes/etc when I hand-water, and the Mylar is extremely easy to clean up... (And since I'm keeping the lights fairly closer, the Mylar can reflect a decent bit of useable light, so it's probably good to leave it uncovered.)

    The main problem is that it's a pain to hand-water these things with the leaves growing down! So is this more of a normal thing to happen to bottom leaves on every single grow, or is it perhaps being caused or exacerbated by the reflective Mylar base of my grow tent?

    Edit: Downloaded pics from my camera...you can see the lower leaves completely curling down around the planters, etc! And that's after already pruning several. (Sorry about the white balance, my new LED panel is different weird purple shade overall than the existing one, so I need to calibrate it with a gray card again, and it still won't be right! And I also need to take better pics of the lower leaves, since they're underexposed...) These are in a 4'x4' tent BTW, the wide-angle lens I'm using makes it look smaller than it actually is... :)

    Attached Files:

  2. Lower leaves drooping indicates a problem with air getting to the roots. This can be caused by overwatering, root binding or a poor substrate.
  3. #3 vapeos, May 30, 2012
    Last edited by a moderator: May 30, 2012
    This really doesn't seem like a "drooping" problem, but more that my lower leaves completely curl under and against/into the containers. Yet they still look quite healthy while doing so...

    I'm growing in coco/perlite, so overwatering probably isn't an issue. I also just switched to Smart Pots for this grow, after a couple grows with regular plastic pots.

    So I don't think it's overwatering, since the coco/perlite mixture is, well, hard to overwater! I don't think the substrate is the issue in general due to that; I'm using Cocogro this time as well, so that's a bit higher-quality. Nor do the plants seem to be root-bound; the water uptake has been increasing steadily since starting these plants.

    I would imagine that air getting to the roots isn't an issue either, due to the mix I'm using.

    The only real "bad problem" I have with my plants is that I currently have hard water (~650 - 700µs)...but they'll still grow with that; I've only seen slight nute burn on one of three plants. (Working on getting an RO system installed.)

    I'm still suspecting that those lowest leaves are "seeing" the light reflected off the Mylar, and thus growing down...or not?

    Really, these plants look pretty damn healthy (considering my hard water!) as far as growth goes...but those bottom leaves just keep curling way down.

    Edit: I have seen much more nute burn on my previous couple attempts...perhaps due to the hard water bumping up the EC so much. (Hopefully I get my RO system working soon!) Only one of my current plants is showing mild symptoms, and I backed off on that one, but I still have to wonder if those lower leaves are growing towards the Mylar, being shaded under other leaves with my LED panels less than 1' away...
  4. you found a solution to this common problem ?

    i dnt think it has smth to do with mylar reflection tho u could put cfl there and same result.. maybe air circulation ?

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