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(URGENT HELP!) Leaves are yellowing and drying out quickly

Discussion in 'Growing Marijuana Indoors' started by Galahead, Jun 2, 2020.

  1. #1 Galahead, Jun 2, 2020
    Hello! I have a few autos: northern lights and royal gorilla (RQS), 6 plants total. They are around the 3-5 week of flower, and supposedly still need about 3-4 more weeks.

    The problem: at the beginning of flower, some of the lower leaves started to get yellow and dry out until they fell down. At the beginning there weren't many, but now it keeps "spreading" and more and more leaves are yellowing, to the point that its getting close to the buds and endangering them. It seemed to be a nitrogen deficiency, so I started giving more nitrogen nutrients to see if they improved. It didnt work, the leaves kept drying out and they started to show symptoms of overfeeding, with the tips of leaves getting burned and yellow.

    About the grow conditions: I use a 250w HPS, all mix soil from biobizz, nutrients are all biobizz (root juice on the first weeks, grow, bloom, and the algae one). I water about every 2-3 days following the biobizz schedule, always with some nutes. One issue is that the temperature has been a bit high, with summer approaching western europe way too quickly I dont have much control over temperature, even using a cooltube and a strong exhaust system. Although they dont show too many signs of heat stress.

    I believe it could be a PH issue, since I havent done measurings; or the heat is worsening some issue; or could I have an overdose and at the same time and underfeeding of nutrients?
    I really hope this can be fixed somehow, or that the leaves can have enough time to get their strength back!
    Thanks in advance for anyone who can help!
    Here are some pictures:
    20200602_093334.jpg 20200602_093355.jpg
     
  2. #2 MickFoster, Jun 2, 2020
    3 threads.......really?
     
  3. #3 Galahead, Jun 2, 2020
    yeah, felt quite urgent, ive tried many things but they just keep dying out, scared that the plant is at serious risk. I can delete some if it goes against the rules, though.

    Any ideas on the plant issue?
     
  4. #4 MickFoster, Jun 2, 2020
    It looks like it's fried. You don't add more nitrogen in flower.......you use less.
    I'm not a soil grower but it looks overfed and fried.
     
    • Like Like x 1
  5. #5 mactheman, Jun 2, 2020
    @MickFoster has hit the nail on the head ,,,fan leaves do start to yellow in flowering cannabis ,its just using up the N in the plants leaves ,looks like you fed a lot of N nutes ,,just give water and if you do feed use a P/K nutes ,plus you can take the damaged leaves off the plant its not going to hurt the plant,,,,macm
     
    • Like Like x 2
  6. #6 GroBuddy, Jun 2, 2020
    favors heat stress the yellowing and tips curling up. also I don't know about biobuzz but I rotate water feed. anything over 82 degrees can aid in heat stress. nitrogen toxicity leaf tips turn down not up and the leaves become dark and shiny before turning yellow. could be aiding the issue but not the only cause
     
    • Like Like x 1
  7. #7 Galahead, Jun 2, 2020
    Thanks everyone! I'll stop giving nutes. guess it was my fault, should have researched more, I was sure they had a nitrogen deficiency that started with flowering because of the many yellow lower leaves.
    I did give a good amount of N (biobizz grow). From now on I'll just give water with a little bit of bloom nutes and hope they can recover, seems they've lost many potential flowers :/
    Is it possible there is also a PH issue that is worth looking into? I cant afford a PH measuring device right now; I could invest in some of the test kits if necessary

    Also, would flushing them "lightly" right now be a good idea? or would it do more harm than good
     
  8. #8 mactheman, Jun 2, 2020
    no real need to flush just give water with around 25% run off .just water like that every time you water this week give no nutes just yet then when you do give nutes just try half strength when you do feed again ..plant look like it hasnt got to long to go now before harvest ,,,,mac,
    PS watch the temps in there as well like GroBuddy as said
     
  9. #9 Galahead, Jun 4, 2020
    Hey, thanks for the tips and help! the plants seem to be doing better, got really spooked when I saw most of the lower leaves were dead. the one in the picture is the fastest maturing one I got, seems like itl'll go for another 2 weeks or so. Any ideas on how to reduce the temps? its summer here and I cant really do much. I already got a cooltube and a pretty strong extractor, but the heat seems to be around 30c. Would keeping a wet towel close to the intake help bring in cooler air? or maybe just putting more fans inside? Ideally I`d get a Co2 thing or something to control humidity but i cant afford anything right now
     

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